Hydraulic pump failure reason analysis and troubleshooting method

Hydraulic pump failure reason analysis and troubleshooting method

Hydraulic pump as the energy device of hydraulic system, occupies a very important position in the hydraulic system, if the failure of hydraulic pump, it will affect the normal work of the whole hydraulic system. 

1. The oil pump can not suck oil

Cause 1: The oil inlet and outlet are reversed. Elimination method: select the correct connection method according to the instructions. Reason 2: oil viscosity is too high, so that the blade movement is not flexible. Elimination method: choose the recommended viscosity of the working oil. Reason 3: The oil temperature is too low, so that the oil viscosity is too high. Elimination method: heating to recommended normal working oil temperature. Cause 4: blockage of suction pipe or filter device causes poor oil absorption. Elimination method: clean the pipeline or filter device, remove the blockage, replace or filter the hydraulic oil in the tank. Reason 5: High filtering accuracy of suction inlet filter leads to poor oil absorption. Elimination method: according to the instructions of the correct selection of filters. Cause 6: The blade is stuck in the slot due to the low filtration accuracy of the system oil. Elimination method: disassemble, repair and grind the internal parts of the oil pump, reinstall carefully, and replace the hydraulic oil. Cause 7: The suction of the small displacement oil pump is insufficient

Elimination method: Fill the pump with hydraulic oil. Cause 8: Air leakage in the suction pipe. Elimination method: check the joints of the pipeline, and seal, firm.

2. The flow is not up to the rating

Cause 1: The speed does not reach the rated speed. Elimination method: Choose the generator speed according to the rated speed specified in the manual. Cause 2: A leak occurs in the system. Elimination method: check the system, repair the leak point. Cause 3: The screw of the pump cover loosens due to the long-time operation and vibration of the oil pump. Elimination method: properly tighten the screw. Cause 4: Air leakage in the suction pipe.

Elimination method: check each connection, and seal, tighten. Cause 5: The oil level in the tank is too low and the oil absorption is insufficient. Elimination method: Add oil to the lowest oil mark above. Cause 6: The inlet oil filter is blocked. Elimination method: clean the filter or choose an oil filter with a flow rate more than 2 times that of the oil pump. Cause 7: The suction pipe is blocked or small in diameter. Elimination method: Clean the pipeline, choose not less than the oil pump inlet diameter suction pipe. Reason 8: Oil viscosity is too high or too low. Elimination method: choose the recommended viscosity of the working oil. Cause 9: The variable pump flow is improperly adjusted. Elimination method: Adjust to the required flow.

3. The pressure won’t go up

Reason 1: The oil pump is not filled with oil or the flow is insufficient. Elimination method: Fill the pump with working oil. Cause 2: The adjusted pressure of the relief valve is too low or faulty. Elimination method: adjust the relief valve pressure or repair the relief valve. Cause 3: A leak occurs in the system. Elimination method: check the system, repair the leak point. Cause 4: Because the oil pump vibrates for a long time, the screw of the pump cover loosens. Elimination method: properly tighten the screw. Cause 5: Air leakage in the suction pipe. Elimination method: check each connection, and seal, tighten. Cause 6: Insufficient oil absorption. Elimination method: Fill the pump with working oil. Cause 7: The variable pump pressure is improperly adjusted. Elimination method: Adjust to the required pressure.

4. The hydraulic oil in the hydraulic pump becomes white, cloudy and has bubbles.

Cause 1: The connection pipe of the hydraulic pump is aging and the connector is loose. Elimination method: The rubber seals should be replaced and the joints tightened. Reason 2: The hydraulic oil in the tank is not enough. Elimination method: Standard hydraulic oil should be added to the specified value. Cause 3: The oil filter is blocked. Elimination method: the screen should be replaced to remove foreign bodies. Cause 4: Water is mixed with hydraulic oil. Elimination method: hydraulic oil should be replaced, or the original hydraulic oil to do water removal treatment.

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