Information about Idler in Excavator
The idler on excavator is one of the important members of the excavator accessories. Its usage makes the excavator work more dynamic. The working principle of the guide wheel assembly of the excavator accessories is as follows: use the grease gun to inject the grease into the grease cylinder through the grease nozzle, make the piston extend to push the tensioning spring, move the guide wheel to the left to tighten the track, and the jacking spring has an appropriate stroke, When the tension force is too large, the spring is compressed to buffer; After the excessive tension force disappears, the compressed spring pushes the guide wheel to the original position, which can ensure the sliding along the track frame to change the track width, ensure the disassembly and assembly of the track, reduce the impact in the walking process and avoid the derailment of the track chain.
Reasons of Damage
However, excavator accessories are also damaged. Generally, the damage of mini excavator idler is mainly caused by poor lubrication of idler shaft. The main reasons are as follows:
1. It is that the different axial degrees of the bimetallic sleeve sliding bearing of the guide wheel are out of tolerance, and the crawler walking produces vibration jump and impact. Once the geometric dimension is out of tolerance, the clearance between the guide axle and the shaft sleeve is too small or no clearance, and the lubricating oil film thickness is not enough or even no lubricating oil film.
2. The surface roughness of the guide axle is out of tolerance. There are many metal ridges on the shaft surface, which destroys the integrity and continuity of the lubricating oil film between the shaft and the sliding bearing. During operation, a large amount of metal wear debris will be generated in the lubricating oil, which will increase the surface roughness of the shaft and bearing and worsen the lubrication state, resulting in serious wear of the guide axle and sliding bearing.
3. It is the defect of the original structure. The lubricating oil is injected from the screw plug hole at the end of the idler shaft, and then gradually fills the whole cavity. In actual operation, if there is no special tool for oil injection, it is difficult for the lubricating oil to pass through the circuitous cavity in the idler only under the action of white body gravity, and the gas in the cavity is not discharged smoothly, so it is difficult to fill the lubricating oil. The oil filling space of the original machine cavity is too small, resulting in a serious shortage of lubricating oil.
4. It is because the lubricating oil in the clearance between the guide axle and the shaft sleeve has no oil passage and can not take away the heat generated by the bearing work, resulting in the increase of the working temperature of the bearing, the decrease of the viscosity of the lubricating oil and the decrease of the thickness of the lubricating oil film.
These are several possiblee reasons that may damage our idler. If you have any ideas, please feel free to let us know.
