Troubleshooting of ABG423 paver two cases       

1. hydraulic oil deterioration

After 1 ABG423 paver no-load tester running 10min, a large number of hydraulic oil overflow from the fuel tank cover exhaust port. See from the mirror to observe the level of hydraulic oil tank of hydraulic oil mixed with a large number of bubbles, and the change of color has become deep black.

The analysis shows that the reason for the bubble in the hydraulic tank is usually due to the low oil level of the tank or the lax sealing of the suction pipe of the hydraulic pump, leading to the suction of the hydraulic pump. The reason for blackening of hydraulic oil is usually due to excessive oil temperature, causing oxidation deterioration.

First, check the oil level of the hydraulic tank is normal.

Secondly, maintenance of hydraulic pump oil suction tube seal. The hydraulic tank of the paver has 9 oil suction pipes and 5 oil return pipes. Replace the oil suction pipe and seal which may leak, fasten the tubing joint which may be loose, and eliminate the possibility of oil leakage in the oil suction pipe.

Again, replace the hydraulic oil after testing machine, the fault is still. Check the replacement of hydraulic oil, found that the oil is not only deterioration, and the color is obviously black, judging that there may be engine oil mixed with hydraulic oil. Further observation and analysis, the hydraulic system is only double gear pump installed directly on the engine cylinder block. When the gear oil seal of the double gear pump is damaged, the air and blackening oil may be sucked from the spindle head when the gear pump sucks oil.

Finally, replace the gear oil seal of the double gear pump and re test the machine, no bubbles in the oil. One month later, the color of hydraulic oil was observed, no black phenomenon occurred, and the failure disappeared.

Rotation abnormality of 2. screw feeder

The left screw conveyor of 1 ABG423 paver rotates slowly, and the right screw feeder does not turn failure.

The left and right screw conveyors are driven by 2 independent hydraulic systems, which consist of a variable pump and a fixed motor. The electro-hydraulic proportional solenoid valve controls the speed of the quantitative motor on the side by adjusting the flow rate of each variable pump. The output power of the left side quantitative motor is transmitted to the screw feeder through the planetary reducer and chain.

According to the working principle of the screw conveyor, according to the sequence of the electronic control system, hydraulic system and mechanical transmission part, the fault is gradually found.

First, push the left and right electro hydraulic proportional solenoid valve core with the six angle wrench, and open the valve core to the maximum, and the fault is still the same. The possibility of failure caused by the electronic control system is ruled out.

Secondly, on the left and right variable pump pressure outlet are respectively connected with a pressure gauge (pressure range is 0 ~ 40MP, a) with six angle wrench are open on both sides of the electro-hydraulic proportional solenoid valve spool, the measured maximum pressure on the left and right side of the variable pump was greater than 30MP a, which indicates that the hydraulic system no fault. Because the electrical control and hydraulic system are not found fault, the basic fault can be identified in the mechanical transmission part.

Thirdly, the inspection hole of the chain drive box of the screw conveyor is opened, and it is found that the lubricating oil in the chain transmission gear is seriously insufficient, and there is a large amount of dry ash. The analysis results show that the dry ash in the mixture enters the chain box due to the damage of the seal of the chain transmission box, and the accumulated dry ash will cause the drive chain to be jammed.

Finally, the chain transmission box disintegrated, will be one of the dry ash wash, replacement of bearings, seals, and lubricating oil after the test machine, spiral feeder work.