Performance characteristics of vane pump
Compared with other hydraulic pumps, the vane pump has the following advantages: compact structure; The bearing bearing force of fixed displacement vane pump is balanced, the flow is uniform, the noise is small, and the service life is long; Single acting vane pump can be made into variable displacement pump; Both single acting and double acting pumps can be made into duplex pumps; Disadvantages of vane pump: high requirements for cleanliness of oil; The stator structure of the double acting vane pump is complex, the rotor of the single acting vane pump bears the unilateral hydraulic unbalanced force, and the bearing life is short;
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Fault phenomenon
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Cause
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Exclusion method
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1. The pump does not deliver oil or has no pressure
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(1) The rotation direction of the prime mover and the oil pump is inconsistent or the transmission key is missing
(2) The oil inlet and outlet are installed reversely
(3) Pump speed too low
(4) The viscosity of the oil is too high, and the vane pump cannot move flexibly
(5) The oil level in the oil tank is too low, and the suction pipe is exposed
(6) Too low oil temperature makes the oil viscosity too high
(7) Blockage of suction pipe or filter device causes poor oil suction
(8) Poor oil suction due to high filtering accuracy of oil suction filter
(9) The low oil filtration accuracy of the system causes the blade to jam in the groove
(10) Insufficient oil suction of small displacement oil pump
(11) Air leakage due to poor sealing of suction pipe
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(1) Correct the steering or reinstall the drive key
(2) Select the correct installation method according to the instructions
(3) Increase the speed to above the minimum speed of the pump
(4) Select hydraulic oil with recommended viscosity
(5) Replenish the oil above the minimum oil mark
(6) Use after heating to proper viscosity
(7) Disassemble, wash and repair the internal parts of the pump, carefully reassemble them, and replace the oil
(8) Clean the pipe or filter device, remove the blockage, replace or filter the oil in the oil tank
(9) Select the filter correctly according to the product manual
(10) Fill the pump with oil
(11) Check the pipe quality and the sealing condition of all connections, replace the pipe or improve the sealing
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2. Insufficient flow
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(1) The speed does not reach the rated speed
(2) Leakage in the system
(3) The pump cover screws are loose due to the long time operation and vibration of the pump
(4) Air leakage of suction pipe
(5) Insufficient oil absorption
① The liquid level in the oil tank is too low
② The inlet filter is blocked or the overflow is too small
③ The suction pipe is blocked or too small
④ Oil viscosity is too high or too low
(6) Improper flow regulation of variable displacement pump
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(1) Select the motor speed according to the specified rated speed in the manual
(2) Check the system and repair the leaks
(3) Tighten the screws properly
(4) Check all connections and seal them tightly
(5) Perform the following operations
① Replenish the oil above the minimum oil mark
② Clean the filter or select a filter whose flow is more than twice the pump flow
③ Clean the pipeline, and select the suction pipe that is not smaller than the pump inlet diameter
④ Select hydraulic oil with recommended viscosity
(6) Readjust to required flow
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3. The pressure cannot rise
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(1) The pump does not feed oil or the flow is insufficient
(2) The regulating pressure of the relief valve is too low or fails
(3) Leakage in the system
(4) The pump cover screws are loose due to the long time operation and vibration of the pump
(5) Air leakage of suction pipe
(6) Insufficient oil absorption
(7) Improper pressure regulation of variable displacement pump
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(1) Same as above
(2) Re adjust the pressure of the relief valve or repair the relief valve
(3) Check the system and repair the leakage point
(4) Tighten the screws properly
(5) Check all connections, seal and fasten them
(6) Same as above
(7) Readjust to required pressure
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4. Leakage
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(1) Seal aging
(2) Loose oil inlet and outlet connections
(3) Bumping seals or sand holes in the pump housing
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(1) Replace seals
(2) Tighten the pipe joint or flange screw
(3) Repair the sealing surface or replace the housing
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5. Excessive vibration noise
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(1) Poor oil suction or low liquid level
(2) Air intrusion
(3) Oil viscosity is too high
(4) High speed
(5) The pump drive shaft is too large compared with the prime mover
(6) The end face of the oil distribution plate is not perpendicular to the inner hole or the verticality of the blade is too poor
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(1) Clean the filter or add oil to the oil tank
(2) Check the oil suction pipe and pay attention to the liquid level
(3) Properly reduce the oil viscosity
(4) Reduce speed
(5) Adjust the coaxiality to the specified value
(6) Grind the end face of oil distribution plate or improve the verticality of blade
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6. Abnormal fever
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(1) Too high oil temperature
(2) Oil viscosity is too high and internal leakage is too large
(3) The working pressure is too high
(4) Oil return port direct street pump inlet
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(1) Improve heat dissipation condition of oil tank or use cooler
(2) Select appropriate hydraulic oil
(3) Reduce working pressure
(4) The oil return port is connected below the oil tank page
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