In the process of using crawler excavator, some excavator walking faults will be encountered. Most of the reasons for the traveling faults of excavator are related to the traveling motor. This article summarizes several common faults caused by the traveling motor, explains the causes of the faults, facilitates self inspection and maintenance, and is only for reference.
1. Walking without high and low speed
The high-speed and low-speed switching of the excavator can be realized on the display screen, which is linked with the solenoid valve group of the accumulator, that is, the high-speed and low-speed traveling solenoid valve. The hydraulic oil supplies oil to the left and right traveling motors respectively through this valve. After entering the motor, the variable speed valve spool works, and the motor can be accelerated.
Therefore, when there is no high-speed or always high-speed and no low-speed traveling fault, first check the valve core and coil of the traveling high-speed solenoid valve, and then check the variable-speed valve core on the traveling motor.
2. Inability to walk on one side
1) Check the travel motor overflow valve, remove it for cleaning, or exchange it with the normal side, and check whether the fault is transferred.
2) Check the balance valve of the travel motor cover and the internal components of the travel motor. The wear and internal leakage of the balance valve and the wear of the internal components of the motor will cause the failure of single side walking.
3) Check the central swivel, aging oil seal and internal wear, which will cause the failure of single side walking.
4) Check whether the pilot pressure on the weak side is normal. If there is a problem, check whether the foot valve is worn and has internal leakage.
3. Downhill travel overspeed
For example, the right motor can move forward, but there is no action when moving back. When walking on the slope, the walking speed on one or both sides is too fast to control. In case of the above faults, it is necessary to check the balance valve and one-way valve of the traveling motor, brake piston and brake pad.
4. Shake when stopping operation
Raise the excavator boom to the highest position, the middle boom can be retracted, directly lower the boom to half, then stop lowering the boom, and observe whether the excavator swings up and down severely. If the shaking is severe, it is because the rotating bearing clearance is too large. This method is used to test the upper and lower clearance. There is another way to test the clearance of rotating bearing teeth. Turn on the small throttle, then rotate left and right and suddenly stop to observe whether the left and right shaking is severe. If the shaking is severe, it can be judged that the rotating big teeth are worn too much to produce clearance. Generally, these are the main reasons for shaking of loading and inaccurate parking.
