When the excavator walks slowly, many people don't know how to check and find out the cause of the fault. A total of 9 causes of slow walking are summarized. This article will describe four causes of faults caused by slow walking of excavator and corresponding troubleshooting methods for reference only.
1. The sealing ring of the center swivel is damaged
The central swivel joint is composed of a shell and a mandrel. The mandrel is installed on the lower vehicle body, the shell is installed on the upper vehicle body, and an annular groove equal to the oil pipe is opened on the mandrel. The hydraulic oil from the main valve core flows to the motor from the vertical hole on the mandrel through the housing. The housing rotates continuously with the upper vehicle body. The groove on the mandrel can also keep unblocked with the oil port on the housing, and the hydraulic oil can enter and exit freely on the central joint. If the filter element of the hydraulic oil is not replaced in time, the bypass valve on the filter element may be opened, and the hydraulic oil is not filtered, so that the impurities in the oil directly enter the sliding surface of the central swivel joint, resulting in the damage of the sealing ring on it. During the walking of the excavator, the speed of the walking motors on both sides is different due to the leakage of pressure oil on one side, resulting in the deviation of the excavator. The troubleshooting method is to replace the hydraulic oil and filter element at the same time when replacing the oil on the center swivel.
2. Dirt enters the balance valve in the parking brake oil circuit on one side of the excavator
When the excavator is walking, if dirt blocks the small hole of the balance valve, the parking brake cannot be released, resulting in walking deviation. This is because when the excavator is walking, if the pressure oil cannot enter the spring chamber of the balance valve through the small hole of the balance valve to push the balance valve core to move, the pressure oil cannot enter its hydraulic system through the groove on the balance valve, As a result, the parking braking force cannot be released, and as a result, the traveling motor cannot rotate, so there will also be traveling deviation. The removal method is to remove the balance valve and clean it. No dirt can enter during disassembly and assembly, and then replace the required hydraulic oil and filter element regularly.
3. The travel motor safety valve leaks oil
Oil leakage from the travel motor safety valve will lead to low pressure in the system, insufficient rotation angle of the travel motor and travel deviation. The troubleshooting method is to replace the damaged travel motor safety valve. When judging, the safety valves of the left and right travel motors can be replaced to see whether they deflect during reverse travel.
4. Dirt blocks the small hole K of the balance valve of the final drive system, so that the parking brake cannot be released
When the excavator is walking, if the pressure oil cannot push the balance valve core to move through the small hole K on the balance valve, the pressure oil cannot release the parking power through the groove on the balance valve, resulting in the normal rotation of the walking motor and the deviation of the excavator. The elimination method is to clean the oil circuit, pay attention to avoid dirt during disassembly in the future, and replace the hydraulic oil and filter element on time.
