The elimination of roller walking and vibration failure

A 219D-2 vibratory roller manufactured by BOMAC, Germany, which fails to walk and vibrate completely after working at 2000h. The symptom is that the machine can not move or vibrate when it needs to press another operation surface after it is stopped. This fault comes very suddenly, the operating system in advance has not alarm, and there is no other abnormal phenomenon.

We press the "Jane to the complex" principle of troubleshooting, first of all, to check the relevant mechanical parts of the roller, and found no abnormal phenomenon. As the fault occurs suddenly, it is possible to determine the fault on the hydraulic or electrical system. Then, check the hydraulic oil tank, the hydraulic oil is sufficient, no deterioration, oil viscosity is also normal, cleaning the hydraulic oil filter also found no impurities; touch the walking motor and vibration motor, also did not feel overheating; pressure gauges in the system pressure test port measured inlet pressure. Results with the rated pressure system was consistent with that of hydraulic system pressure is normal; the observation hole opened on both sides of the wheel vibration, that vibration bearing and the connecting sleeve intact, vibration of shaft end is not unusual; finally, the detection of the electrical system, one by one investigation, found that the roller of the power generator.

The roller is closed by the generator, remove the generator, the resistance between the terminals with a multimeter to detect the value of the generator, are to meet the requirements; detection of rotor field winding and stator windings, were not found to have short circuit, open circuit and ground; detection of brush assembly, found in a brush holder the brush is worn out, by the spring pressure on it has not been able to make the brush contact, so the generator can not generate electricity. The brush of the generator is a carbon brush. When the brush is replaced, the generator will return to normal power generation, and then the machine will be out of order.

After further analysis, it is learned that there is a brake electromagnetic valve and a vibration electromagnetic valve in the electrical system of the machine. When the roller stops, the two valve closes automatically. After restarting the roller, if the generator of the roller does not generate electricity, the power stored by the accumulator of the 12V alone can not open the two valve, so the fault occurs.