If the hydraulic system fails, finding the problem is not an easy task at all. The hydraulic system is composed of individual components, and these components may be the source of failure. Therefore, we have listed some common problems in hydraulic systems, which you can find out.
1. No oil pressure
There is no pressure in the hydraulic system: the rotation direction of the hydraulic pump is opposite or the hydraulic pump has no liquid output; The overflow valve spool on the electro-hydraulic proportional device is stuck and the damping hole is blocked; The oil suction port of the oil pump is not unobstructed and the oil suction filter is blocked; The pressure valve is dirty and the poppet valve cannot be closed.
Solution: correct the rotation direction of the hydraulic pump, troubleshoot the hydraulic pump fault; The relief valve is dismantled and cleaned. The valve core is required to move flexibly in the valve body, and the damping hole is blown through with compressed air. Clean the filter element, and check whether the suction pipe is blocked; Disassemble the pressure valve and remove the poppet spool for cleaning.
2. The oil pressure is not enough.
The reason is that there is air inhalation in the hydraulic system, and the oil in the tank has a lot of foam, or the overflow valve and the electromagnetic reversing valve leak.
Solution: Check whether the oil suction port of the hydraulic station leaks oil; Whether the hydraulic fittings at the suction of the pump is tightened; Check whether the pipeline between the oil suction filter and the oil suction port of the oil pump leaks; Check whether the oil pump end cap screw is tightened; Clean the overflow valve spool. If the overflow valve spool is not flexible in the valve body, you can hold the spool by hand and grind it back and forth in the body; To clean the solenoid directional valve spool, the spool is required to move flexibly in the valve body to ensure that the spool is in place when working.
3. The oil pressure is not stable.
After long-term use, there is a large amount of leakage between the oil collecting routes in the safety braking device, and between the valve and the oil collecting route, and the oil pressure drop leads to the loose valve, because the screw between them is loose, and the screw can be tightened to eliminate the fault; The reason for the oil pressure instability in the hydraulic station is that air is mixed into the hydraulic system, which should be excluded, or the current filtering of the coil of the electro-hydraulic pressure regulating device is not good. The coil vibrates up and down, resulting in oil pressure instability. The electrolytic capacitor can be installed to strengthen the filtering.
4. The residual pressure is too large
Residual pressure will make the brake lose its function, the main reason is: the nozzle distance of the baffle on the control rod of the electro-hydraulic pressure regulating device is too small; The overflow valve orifice is too large.
Solution: Adjust or replace the upper baffle plate of the control rod; Replace the relief valve orifice with a smaller diameter.
5. Failure of holding performance of second brake oil pressure value
The large overflow valve on the oil circuit block of the hydraulic station has stolen goods stuck so that the valve core is not closed properly; The opening of one-way throttling cut-off valve is too large, a large amount of oil is discharged; There are stolen goods in the solenoid reversing valve, and the leakage is too large.
Solution: For this kind of fault, the spool can be removed for cleaning, remove the stolen goods, so that the spool is in place, and then adjust the one-way throttling cut-off valve to make its opening as small as possible, and play the role of throttling oil filling the hydraulic cylinder.
