Reasons and solutions for deviations of subminiature excavators

Reasons and solutions for deviations of subminiature excavators

2020-11-26 10:39:19  edit:xiaoli

Let's take a look at some of the reasons for deviations in ultra-small excavators.

Reasons and solutions for deviations of subminiature excavators

1. The seal of the central rotary joint is damaged

2. The balance valve in the parking brake oil circuit on the side of the excavator

3. Travel motor safety valve.

4. Leakage, dirt blockage, and finally drive system balance valve

5. The main valve of the excavator failed to deflect.

6. The suction valve on the deflection side of the excavator is damaged.

7. The tension on the track is different.

8. The plunger of the oil pump flow regulator is stuck.

9. The output pressure of the proportional valve is too low.

The maintenance ideas and methods for the running deviation of the subminiature excavator. When the operation deviation of the subminiature excavator occurs, it is recommended to check the crawler tension of the subminiature excavator first, then check the walking motor and main pump, and finally check the pilot oil circuit and distribution valve, and use the elimination method to find the true deviation of the subminiature excavator the reason.

1. Check whether the tension of the two tracks is consistent. Support the two tracks respectively, and check whether the distance between the sinking of the track and the horizontal line of the chassis is within the standard range (the road surface is generally 320-340mm, the dirt road is 340-380mm, and the sand, gravel and snow are 380mm).

2. Check whether the pilot pressure of the pump before and after the dashboard is consistent.

3. The motor high pressure oil pipe is interchangeable with the center joint. If the fault phenomenon changes during the test, the right-hand drive motor may malfunction, otherwise the right-hand drive motor may malfunction. Then, the walking motor should be disassembled for inspection to find out the cause of the failure.

4. Replace the four tubes between the main control valve and the left and right stroke intermediate joints. If the fault changes during the test, the central connector may malfunction. Otherwise, the central connector will malfunction. It should be disassembled for inspection and the cause of the failure should be determined.

5. Check the spool of the left and right stroke control valve. It is found that the spool is flexible and there is no damage in the valve body. The control valve can be cancelled. 6. After the two main pump regulators are exchanged, replace the testing machine. If the running deviation fault changes, it can be judged that the fault is in the regulator, otherwise the fault should be in the hydraulic main pump.

7. If the spring in the main valve is soft or damaged, or the valve core is stuck, it may cause the oil pressure to drop and operation deviation. During inspection, measure the pressure in the main valve oil circuit, the normal value is 32.5 MPa

Four methods to judge oil intake

1. Observe the appearance of the excavator oil. It is easy to judge whether there is water in the oil. Oils that do not contain water are translucent oils, and oils that contain water are opaque brown or khaki.

2. Check whether the engine oil in the excavator coolant contains engine oil. If some parts of the engine are damaged, the engine coolant will enter the lubrication system and the oil will mix. Penetrating oil can also be found in the tank coolant and is easy to identify.

3. If the engine oil enters the water, it will chemically react with the coolant in a high temperature environment to form an emulsion. Check whether the dipstick shows white foam. 4. When the excavator oil contains a lot of water, the oil level will rise. At this point, we can simply judge the oil level.

This is the reason for the deviation of the ultra-small excavator and the method of judging the oil intake.

Copyrigh: MINI Excavators&Crawler Hydraulic Excavator