Details: Boss Yang said by phone that "the internal and external leakage of the excavator gear pump is large". Further communication knows: Boss Yang Hitachi ZX60-5A excavator was under construction in the scenic spot and has not been repaired before. Recently, the excavator has appeared inside the gear pump 3. The phenomenon of large external leakage.
Failure analysis:
The main part of the internal leakage is between the pump cover and the gear end face, the side plate and the gear end face, or the floating sleeve and the gear end face. The oil pump casing is worn.
Troubleshooting:
1. Check whether the corresponding contact surface is worn or scratched or the gap is large to cause serious internal leakage (the internal leakage caused by it accounts for 50% to 70% of the total). If found, the damaged part should be repaired immediately.
2. Check whether the pump body is subject to a certain amount of wear, or whether the oil is dirty to cause the wear between the relative moving surfaces, thus causing the phenomenon of "inner leakage".
3. After further inspection, it was found that the cause of the failure was that the low-pressure chamber inside the pump body was partially damaged, and the oil was not clean. After corresponding treatment, the failure disappeared.
