The boom motion of the excavator is one of the most frequently used motions in daily construction. If the boom is slow and weak to lift, it will basically be declared that it needs to be stopped for repair.
The excavator boom can not be repaired:
1 Check the blockage of oil circuit
Remove the oil pipe, remove the boom slide valve body, valve rod and related components for cleaning, clean the oil passage and blow it with compressed air.
2 Check the oil circuit for leakage
The leakage of hydraulic system usually occurs after a period of use. Seen from the surface phenomenon, it is mainly caused by seal failure, damage, extrusion, or strained sealing surface The main causes are: oil pollution, improper sealing surface roughness, unqualified sealing groove, loose pipe joints, increased clearance of mating parts, high oil temperature, deterioration of sealing ring or poor assembly. Leakage is divided into internal leakage and external leakage, and usually the failure is mainly caused by internal leakage.
3 Treatment of internal leakage
The internal leakage in this part mainly occurs in the boom spool valve and the oil cylinder. The internal leakage mainly occurs in the valve body and the oil cylinder, which is difficult to check. However, we can use some auxiliary methods to judge the leakage.
4 Inspection of boom oil cylinder
After the boom cylinder piston is retracted to the bottom, remove the oil pipe in the rod less chamber to make the rod chamber of the boom cylinder continue to be filled with oil If a large amount of working oil escapes from the oil pipe port of the non rod cavity, it indicates that the hydraulic cylinder has internal leakage; It can also make the bucket full of load, lift it to the limit position, place the boom control lever in the middle position, shut down the engine, and observe the sinking speed of the boom; Then, place the boom control lever at the rising position. If the boom sinks faster, it also indicates that the internal leakage occurs in the hydraulic cylinder; If the change of sinking speed is not obvious, the internal leakage is caused by the boom slide valve.
At this point, I believe that you have a new understanding of the failure of the arm's inability to move. After all, this failure can often be encountered in real construction operations, and the inspection process delays time, not to mention that it is also difficult to repair. Therefore, we need the professional excavator maintenance technician Fu to solve it for us, so as to ensure the orderly construction progress!
