The essential thing to open an excavator is the daily maintenance and maintenance of faults. Before, I learned that many excavator masters do not know how to solve some common failures. Here, I sort out some questions and answers about the maintenance of excavators, hoping to solve the problems for you:
1.What should we pay attention to when grinding the gear end face
Gear pump gear wear, to use a high precision grinder grinding, to find a strong sense of responsibility of the master operation. For example, the grinding table should be absolutely clean and no dust is allowed on the platform. Because the table is slightly unclean, it will make the grinding plane and the vertical line of the bearing hole offset.
2. What should we pay attention to when assembling gear pump?
The wear of pump shell will be a little more in the Oil Recess. If the pump shell is symmetrical, it can be reversed by 180. To use again. For passive Gear, the two ends should not be replaced. When it is removed, it should be marked.
Because the gear will wear on one side. The active tooth is integrated with the rotating shaft and cannot be turned over; The contact point of the meshing line of two gears can be changed when the passive teeth are turned over. Pump assembly is completed, to add a little lubricating oil before using the hand to rotate slightly, feel smooth.
3. Whether the bearings on the end face should be replaced at the same time during assembly?
Be sure to replace them at the same time. Because of the wear of the pump end face, the main bearing clearance is too large, causing the gear to swing in rotation.
4. After inspection, the damping hole is not blocked. Why can't the pressure of the safety valve be adjusted?
This situation is mostly due to the cone valve and the seat closed loosely, so that the oil pressure of the C chamber can not be established.
5. How to know that the perpendicularity of the ground gear plane and the bearing hole has changed?
Can only be found in the assembly of gear pump, because the clearance of the end face is very small, generally about 0.05mm. The maintenance excavator is familiar with more than a dozen kinds of imported excavator maintenance knowledge, including technical parameters, maintenance data, structural characteristics, hydraulic schematic diagram, electrical schematic diagram and fault diagnosis method, etc. If the end face and the bearing hole perpendicularity change, the pump assembly gear shaft can not move. If the locking screw is loose a little, but it is still not smooth, and then dismantle the gear pump, and there are scratches on the end face. This is the plane of the end face and the bearing hole is not perpendicular.
6. One side of the track can only move forward but not backward?.
Is the overload overflow spool in the walking motor is stuck. In order to protect the safety of the system, two overload relief valves are set in the system. If one of them is stuck in the overflow position, the pressure of the system will be lost.
7. One side of the track moves slowly, but if you make a rotary motion at the same time, the track can be faster. Why?
This failure can happen on a lot of excavators. This is because the flow (in cubic meters per second) supplied to the piston pump of the walking motor is insufficient. When the excavator does another action at the same time, it is equal to the additional flow of a plunger pump. The flow of the two pumps will confluence in Komatsu 200-2 excavator control valve, and Komatsu 200-3 to PC200-6 excavators will confluence on the straight running valve. The lack of flow of the piston pump is not necessarily caused by the damage of the pump, but by the fact that the flow control valve is not adjusted well.
8. pull the excavator walking control handle, feel very heavy why?
The travelling distribution valve is different from other distribution valves. Most of the machines walking distribution valve is not hydraulic control, but through the mechanical pull rod, pulled directly by hand.
As the old machines, or distribution of slide valve has wear and tear, makes walking fitting clearance of slide valve and the hole bigger, high pressure oil from the oil duct through the slide valve clearance leakage to one end of the spring, spring has spring cover cover tightly, make the enclosure formed high pressure, cause the distributing valve to have a spring side shift, joystick is heavy in the other direction (lighter).
9. When the running lever controlling the two tracks at the same time makes the engine speed of the excavator drop or even stop in an instant when it starts, what is the reason?
This failure is quite common. Maintenance excavator excavator structure principle, disassembly and installation methods, fault diagnosis and elimination methods, especially for the use of universal and typical fault diagnosis, elimination methods and the disassembly of excavator parts. The maintenance excavator is proficient in more than ten kinds of imported excavator maintenance knowledge, including technical parameters, maintenance data, structural characteristics, hydraulic schematic diagram, electrical schematic diagram and fault diagnosis method, etc. This is mainly the piston pump variable mechanism has problems. Machine in idle state, the plunger pump still has a large flow.
10.The walking oil motor has just been repaired. The track moves faster when the throttle is small, but it won't go when the throttle is large. What is the remedy?
This is because the maintenance of the valve plate and grinding too much, so that the valve plate and cylinder plane pressure is not enough. Small throttle when the oil pressure is small, between the plane and the plane is not easy to produce leakage; When the throttle is large, the oil pressure increases, resulting in the overflow between the planes, resulting in the track can not move when the throttle is large. The remedy can be added to the spring gasket, if it is a butterfly spring, you can add a butterfly spring.