5 Signs That Your Hydraulic Oil Needs to Be Checked or Replaced

Hydraulic oil plays an important role in hydraulic systems by transmitting power, lubricating components and helping protect internal parts during operation.

However, hydraulic oil does not necessarily need to be replaced after a fixed period of time. Its service life depends on factors such as operating temperature, workload, contamination, system condition and oil quality.

So, how can you tell when hydraulic oil needs to be checked or replaced?

Here are 5 common signs to pay attention to.

1. The oil becomes dark, cloudy or contains unusual deposits

A noticeable change in oil appearance, such as darkening, cloudiness or the presence of deposits, may indicate oxidation, contamination or oil degradation.

However, oil color alone should not be used as the only reason to replace hydraulic oil. The operating condition and oil history should also be considered.

2. Excessive foaming appears in the oil

Continuous or excessive foam on the surface of the hydraulic oil may be related to air entering the system, incorrect oil level, contamination or other system conditions.

If the problem continues, it may affect lubrication and the efficiency of power transmission within the hydraulic system.

3. Hydraulic oil temperature becomes unusually high

If the oil temperature is consistently higher than normal, several factors should be checked, including:

  • Oil viscosity
  • Hydraulic pump condition
  • Filter condition
  • Valves and piping
  • Operating load
  • Cooling system

Changing to a higher-viscosity oil is not always the correct solution. The root cause should be identified first.

4. The machine operates slowly or hydraulic pressure becomes unstable

If the machine becomes slower, movement becomes inconsistent or the hydraulic pressure is no longer stable, the hydraulic oil should be included in the inspection.

Possible causes may include oil degradation, contamination, incorrect viscosity or problems with other hydraulic components.

5. The hydraulic oil has been in service for a long time

Even when the machine is still operating normally, hydraulic oil can gradually lose its performance due to:

  • Oxidation
  • High operating temperatures
  • Water contamination
  • Dust and other contaminants
  • Continuous operation

Regular inspection can therefore help determine when the oil should actually be replaced instead of relying only on a fixed replacement interval.

Sinopec L-HM Hydraulic Oil

Sinopec L-HM Antiwear Hydraulic Oil is an anti-wear hydraulic oil designed for various industrial hydraulic systems.

Depending on the product, available viscosity grades include:

ISO VG 32 | ISO VG 46 | ISO VG 68 | ISO VG 100 | ISO VG 150

When replacing hydraulic oil, always check the equipment manufacturer's requirements and select the appropriate oil type and viscosity grade.

Not every new hydraulic oil can be used as a direct replacement for the oil currently in the system.

Golden Bridge – Sinopec Genuine Lubricants

GOLDEN BRIDGE INTERNATIONAL TRADING CO., LTD. specializes in supplying genuine Sinopec lubricants for industrial machinery and equipment.

Address: 915 Nguyen Trai, Cho Lon Ward, Ho Chi Minh City, Vietnam
Hotline: 0938 296 211 – 0906 805 411
Email: goldenbridgevn84@gmail.com
Website: www.sinopecoil.vn

Looking for Sinopec L-HM 32, 46, 68 or other viscosity grades? Contact Golden Bridge for product information and pricing.

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