Common problems with hydraulic systems include the following:
Pneumatic/oil bubbles
Cavitation
Insufficient pressure
Excessive oil temperature
Oil contamination
Oil emulsification
Accelerated oil deterioration
Failure of the relief valve and servo valve
Frequently clogged filters
Rusted or corroded parts
Abnormal pump noise
Pump and piping oil leaks
Phenomenon: Foam appears in the oil tank and the oil emulsifies, causing noise, vibration, and instability in the pump. This causes the oil to oxidize and lubricity to decrease, resulting in the wear of hydraulic parts.
Cause and Solution:
System leaks: Check seals and pipe fittings.
Low oil level: Replenish hydraulic oil.
Oil quality problem: Use hydraulic oil with a defoamer.
Perfectly designed return line: Make sure the return line is submerged below the oil level.
Improper tank design: Increase tank volume or add a bulkhead to prevent the inlet from being too close to the screen.
System leaks: Check gaskets, pump seals, and pipe connections.
Phenomenon: Bubbles form at the pump inlet and rupture to carry away metal, resulting in localized overheating and pump damage.
Cause and Solution:
Insufficient pump oil, high oil viscosity, low starting temperature
The pump suction inlet position is too high, improper pump size, excessive bending of piping.
Restricted inlet: Clean screens, make sure vents are clear, and check inlet piping size and condition.
Pump higher than oil level: pressurize the the tank or adjust pump position.
Troubleshooting method:
Check the oil pump, filter, piping, and valves for blockage or damage.
Could you confirm that the oil level and oil quality meet the requirements?
Adjust or replace the pressure regulator.
Effects: Reduces oil viscosity, increases leakage, accelerates oil oxidation, and forms “varnish”.
Causes and solutions:
Inappropriate oil: Select oil that meets system design and operating temperature.
Insufficient cooling: Clean the cooler, increase the oil tank, or improve heat dissipation.
Pump wear: Inspect and replace worn parts regularly.
Relief valve set too high: Adjust according to the manufacturer's instructions.
Excessive system load: Avoid overloading.
Phenomenon: Dirt clogs valves, pumps, and actuators, resulting in unstable operation and equipment wear.
Protective measures
Oil tank protection: Ensure that the oil filler screen, cap, and seals are intact and that an air filter is installed.
Oil management: Use clean storage containers and filter new oil to avoid environmental contamination.
Regular Maintenance: Replace wiper rings and seals to prevent internal system contamination.
Filter Inspection: Check the screen and filter regularly to ensure they work properly.
Phenomenon: The oil contains water, leading to corrosion, seal damage, and poor lubrication.
Cause and Solution:
WATER INFILTRATION: Check the sealing of heat exchangers and coolers and install vents containing desiccant.
Environmental water leakage: Improve seals to avoid condensation in the actuator and oil tank.
Measures to remove water: static precipitation, heat separation, periodic draining, use of centrifugal separation or vacuum dewatering equipment.