The essential thing to start an excavator is the daily maintenance and fault repair. It's good to dig out some knowledge questions and answers about excavator maintenance for you. I hope to solve some problems for you:
1. After inspection, there is no wall plug in the damping hole. Why can't the pressure of the safety valve be adjusted?
Most of this is because the cone valve and valve seat are not tightly closed, so that the oil pressure in chamber C can not be established.
2. What should we pay attention to when grinding the gear end face?
After the gear of the gear pump is worn, it is necessary to use a high-precision grinder for grinding, and find a master with a strong sense of responsibility for operation. For example, the grinding table should be absolutely clean and no dust is allowed on the platform. Because the workbench is slightly unclean, the ground plane will deviate from the vertical line of the bearing hole.
3. How to know that the perpendicularity between the ground gear plane and the bearing hole has changed?
4. What should we pay attention to when assembling the gear pump?
The wear of the pump housing will be a little more in the oil inlet chamber. If the pump housing is symmetrical, it can be turned over 180. Reuse. For the driven gear, the two ends cannot be exchanged, and mark it when removing it. Because the gear will wear on one side. The driving gear is integrated with the rotating shaft and cannot be turned over; The contact point of the meshing line of the two gears can be changed by turning the passive teeth over. After the pump is assembled, add a little lubricating oil before rotating slightly by hand, and the feel should be smooth.
5. Should the bearing on the end face be replaced at the same time during assembly?
Be sure to replace it at the same time. The wear of the pump end face is mainly caused by the swing of the gear during rotation due to the large bearing clearance.
6. One track can only move forward, not backward. Why?
It is caused by the overload overflow valve core in the traveling motor being stuck. In order to protect the safety of the system, the traveling motor is equipped with two overload relief valves in the system. If one of the overload relief valves is stuck in the overflow position, the system pressure will be lost.
7. What is the reason why it feels heavy (almost unable to pull) when you pull the travel control handle of the excavator?
The travel distribution valve is different from other distribution valves. The travel distribution valve of most machines is not hydraulically controlled, but directly pulled by hand through a mechanical pull rod. Because the machine is old or the distribution slide valve has been worn, the matching clearance between the travel slide valve and the hole becomes larger, and the high-pressure oil will leak from the oil passage through the slide valve clearance to the end with spring. There is a spring cover outside the spring, which forms high pressure in the cover. As a result, when the distribution valve wants to shift to the side with spring, the control lever is very heavy (lighter in the other direction).
