Symptom:
During the operation of a 7000 hour Komatsu excavator, it is found that the excavator track cannot be tensioned and the excavator deviates when walking. What is the matter?
Place of fault: Anshun, Guizhou
Fault model: Komatsu 200 excavator
Service time: 7000 hours
Fault analysis:
1 grease fitting is blocked.
2. The piston or rod of the tensioning cylinder is rusted and stuck.
Cause of failure:
The track tensioning oil cylinder has not been greased for a long time. Due to the moisture in the butter, the tensioning oil cylinder stays in one position for a long time, which makes it unable to move with the cylinder barrel. Loosen the track grease valve on the relatively tight side until it is completely removed. The grease in the oil cylinder cannot overflow and the track will not automatically relax.
Troubleshooting method:
First, put the bucket on the ground, support the track on one side and hang it in the air. Use a high-pressure grease gun to grease and rotate the track to see if it works. If necessary, use external forces (such as transplanter, bulldozer, etc.) to pull with the rope. If the above methods are invalid, the tensioning cylinder must be disassembled and repaired. The specific methods are as follows:
1 open the track track link (use oxygen to bake the loose pin), take out the guide wheel and tensioner assembly and separate the two parts;
2 pull out the piston rod of tensioning cylinder with the help of tooling and two jacks.
3 carefully remove the rust in the piston and cylinder barrel and clean them. Replace the new sealing components and install the piston back into the cylinder barrel.
4. Assemble the tensioning device with the guide wheel and install it back to the X-frame, restore the track links, tracks and other parts, and re tension the tracks. The maintenance work is completed.
Fault experience: this fault is caused by rust corrosion caused by long-term failure to maintain the tension cylinder. It is necessary to drain oil and re tighten the tension cylinder every 500 hours.
