For the Komatsu PC130-8M0 excavator can't walk problem, you should know the cause of the failure.Of course, there are many types of walking that can't be walked.This article uses examples to explain the reasons and maintenance methods of the left side of the excavator. One of the Case excavators failed to walk on the left during operation.
Specific details: The excavator learned from the operator that the machine had broken the oil seal of the stick cylinder, which caused oil pollution. Disassemble the oil pipe and each spool of the main control valve, clean it and reassemble the test machine. The side is still unable to walk.
Maintenance analysis:
1. The main valve on the left side of the excavator is stuck,
2. The pilot valve on the left side of the excavator is faulty.
3. There is a problem with the walking balance valve on the left side of the excavator,
4. The linear walking valve of the excavator is faulty.
5. The walking motor or reducer of the excavator is faulty.
6. The left walking oil channel at the rotary joint of the excavator is connected in series.
Troubleshooting:
First check the left pilot oil pressure, and use the pressure gauge to measure the oil pressure of the left walking pilot valve at 3.5MPa, which is normal. The left and right pilot pressure oil pipes are swapped and tested, and the fault remains the same, thus eliminating the pilot valve There is a possibility of failure.
Disassemble and inspect the left-hand walking main valve. The other functions of the machine work normally, indicating that the main pump that controls the left-hand walking is normal. Remove the left-hand walking main valve and move the main valve spool by hand to feel that the spool slides smoothly and there is no stagnation. The main valve on the left side was washed several times, and the machine was tested after installation and restoration, and the fault still exists.
Check the balance valve and safety valve, remove the left-hand travel motor, remove the central drive shaft of the reducer, remove the balance valve for cleaning, and then reinstall the test, the machine still cannot walk. Remove the two safety valves on the left motor and the right The safety valve of the walking motor is replaced, and the failure remains after the test.
Disassemble and inspect the linear travel valve, and analyze and believe that if the left travel spool is normal, when operating the left travel of the excavator, the high-pressure oil pipe directly connected to the travel motor should have a large amount of pressure oil. When removing the 1 oil pipe on the left travel motor, operate the excavation When the machine is running, there is almost no oil flowing out of the oil pipe. Although oil flows out of the oil pipe when operating in the opposite direction, but the pressure is very low (return pressure). Considering that every spool has been disassembled, it may be a linear travel valve spool The installation direction is wrong. After installing the spool of the linear travel valve in reverse, the test disappears.
The example failure in this article is caused by the wrong installation of the spool. The reason is that when the spool is disassembled for cleaning or inspection, the installation direction and installation position are not paid attention to. Therefore, during the removal of the hydraulic components, you must remember the installation of each component Orientation, order and position must not be missing, wrongly installed or missing parts, otherwise old faults may not be eliminated and new faults may be added.
