What Is Emulsified Water? | Lubripedia

Emulsified water is water that has been finely dispersed within oil or lubricant, forming a stable mixture that does not separate easily.
Unlike free water, which settles at the bottom, emulsified water is suspended throughout the oil in the form of tiny droplets.
This creates a cloudy or milky appearance and can negatively affect the lubricant’s performance.

How Emulsified Water Forms:

Emulsified water is usually created when water contamination mixes with oil under mechanical agitation, such as in pumps, gearboxes, or hydraulic systems.
High pressure, heat, and turbulence cause the water and oil to blend together, forming a stable emulsion.

Common causes include:

• Leaking heat exchangers or seals
• Condensation from temperature changes
• Poor storage or handling of lubricants
• Washing or cleaning operations introducing moisture

Why Emulsified Water Is a Problem:

The presence of emulsified water in oil can lead to several issues:

• Reduced lubrication efficiency
• Increased wear and corrosion of metal surfaces
• Breakdown of additives and base oil
• Formation of sludge and deposits
• Reduced filter efficiency and clogging
• Risk of microbial growth in storage tanks

Even small amounts of emulsified water can accelerate equipment wear and shorten oil life.

How to Remove or Prevent Emulsified Water:

• Use desiccant breathers and sealed storage containers to prevent moisture ingress.
• Apply centrifugation, vacuum dehydration, or coalescing filtration to remove emulsified water.
• Keep oil systems at stable temperatures to minimise condensation.
• Conduct regular oil analysis to monitor water content and detect early contamination.

Proper maintenance and monitoring help preserve lubricant quality and equipment reliability.

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