What's the matter with the oil leakage of the excavator hydraulic cylinder

 In the daily work of the excavator, the excavator hydraulic cylinder will appear weak and oil leakage. A few days ago, a user called and reported that there was oil leakage in the bucket rod excavator hydraulic cylinder of the Komatsu PC220 excavator, and asked me what happened? What is broken and what parts need to be replaced?

1. Analysis of the reasons for the weakness of the excavator hydraulic cylinder and oil leakage

1. The seal is damaged.

2. The piston rod is pulled out of the groove or the coating of the piston rod is partially peeled off, resulting in oil leakage.

3. The crawling vibration noise of the oil cylinder is caused by the air in the oil cylinder.

2. Excavator hydraulic cylinder weakness and oil leakage maintenance method

Find the cause of the oil leak, and then start how to fix it.

1. Replace the seal.

2. Brush, spray, repair or replace.

3. Exhaust.

3. Matters needing attention in the maintenance process

1. When assembling the end cover of the excavator hydraulic cylinder, first adjust the sealing ring so that it is not tight or loose, and the guide sleeve is concentric to ensure that the piston rod can be moved back and forth by hand (or hit with a hammer), and hang a layer on the piston rod. Oil film.

2. How to prevent poor assembly accuracy of hydraulic cylinders and improve the assembly quality of hydraulic cylinders. For example, when the piston rod and piston are not concentric, correct their coaxiality; when the piston rod is bent, straighten the piston rod. The cooperation between the piston rod and the guide sleeve adopts H8/F8 cooperation. The sealing ring should be used in strict accordance with dimensional standards and quality standards, and should be qualified by regular manufacturers. When using V-rings, the sealing friction should be adjusted to a moderate level.

3. Check whether there is air entering the excavator hydraulic cylinder.

A. If the oil is mixed with air and sucked from the hydraulic pump, the air intake fault of the hydraulic pump can be eliminated first.

B. Replace the new oil cylinder or the repaired hydraulic cylinder, there will be air in the cylinder and the pipeline. The excavator hydraulic cylinder can be operated back and forth several times, so that the hydraulic cylinder enters the hydraulic oil tank for exhaust.