Six Causes and Solutions for Low Pressure in Ropeway Hydraulic Systems

1. Hydraulic oil level too low or oil quality deterioration

Reason: Insufficient oil in the fuel tank and exposed air at the suction port, resulting in the hydraulic pump being unable to build pressure when it is empty; Long term use of oil can cause emulsification, oxidation, and excessive impurities, which can damage the viscosity and lubricity of the oil, leading to increased internal leakage and pressure in the system.

Solution: Check the oil tank level gauge and add specialized anti-wear hydraulic oil for the cableway to the specified level; Replace with brand new qualified hydraulic oil, clean the oil tank, and replace the oil suction and return filter elements to remove air and impurities from the oil.

2. The hydraulic oil pump is severely worn and leaking internally, resulting in a decrease in volumetric efficiency

Reason: The gear pump/plunger pump has been running for a long time, and the internal gears, plungers, and oil distribution plates have worn out. The gap between the sealing surfaces has increased, and high-pressure oil is directly flowing back to the low-pressure side. The pump outlet pressure cannot reach the rated value.

Solution: Use a pressure gauge to measure the no-load and load pressures at the pump outlet. After confirming that the pump body is damaged, replace it with a hydraulic pump of the same model; Inspect the oil suction pipeline to ensure no air leakage or blockage, and ensure smooth oil suction of the pump.

3. Failure of overflow valve pressure regulation or stuck or leaking valve core

Reason: The pressure regulating spring of the overflow valve is fatigued or broken, making it impossible to set the working pressure; The valve core is stuck in the open position by impurities or the sealing surface is worn, and the system pressure continues to unload, always in a low pressure state.

Handling: Disassemble and clean the overflow valve body and core to remove impurities; Replace the damaged pressure regulating spring; Adjust the pressure regulating screw clockwise again, gradually increase the pressure to the rated working pressure of the cableway system, and tighten the nut.

4. There is external leakage in hydraulic pipelines, joints, and valve blocks

Reason: Loose pipeline joints, aging and damaged sealing rings, cracked oil pipes, direct leakage of high-pressure oil to the outside, and continuous loss of system pressure.

Solution: Check the pipelines, flanges, and joints section by section, and tighten any loose parts; Replace aging, damaged O-rings, gaskets, and cracked oil pipes; Perform a pressure holding test after repair to ensure no leakage.

5. Internal seals of actuating components such as oil cylinders and motors are damaged, resulting in excessive internal leakage

Reason: The sealing components and guide sleeve of the oil cylinder piston are worn, and hydraulic oil is flowing between the rodless chamber and the rodless chamber of the oil cylinder; The internal wear of the hydraulic motor and the interconnection of high and low pressure chambers make it difficult to build pressure in the system.

Solution: Disassemble the actuator and replace it with a brand new sealing component; Check the internal leakage of the oil cylinder/motor. If it exceeds the standard, replace the assembly directly and conduct a no-load test run after installation.

6. The solenoid valve core is stuck or the seal is ineffective, and it cannot be closed in the unloaded state

Reason: The valve cores of the reversing valve and unloading valve are stuck by impurities and are in the normally open unloading position; The valve sealing surface is worn, resulting in continuous internal leakage and the system cannot maintain pressure.

Solution: Disassemble the solenoid valve, clean the valve core and valve hole, remove burrs and impurities; Replace damaged solenoid valve seals or directly replace the solenoid valve; Power on and test the valve core to ensure proper switching and no internal leakage.

2026 September 2nd Week VAFEM Product Recommendation

linear bearings:

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