Types of Contamination

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The following photo's show different types of contamination commonly found in oil.
The are magnified 48 times and each scale mark is 45 micron

Type:

Effect:

Type:

Effect:

Mainly rust; white particles: additives

Rapid oil ageing
Breakdowns in pumps & valves
Wear and tear.

Oil ageing products

Blocking of filters
Silting-up of system

Metal swarf

Breakdowns in pumps & valves
Wearing of seals
Leakage
Oil ageing

Particles and swarf in bronze,
brass and copper

Breakdowns in pumps & valves
Oil ageing
Leakage
Wearing of seals

Gel-type residue from filter element

Blocking of filter
Silting-up

Silicates due to lack of, or inadequate, air breather filter

Heavy wear on components
Breakdowns in pumps, valves
Wearing of seals

Coloured particles (red/brown) Synthetic particles (blue)

Breakdowns in pumps & valves

Wearing of seals

Fibres due to initial contamination, open tank, cleaning cloths etc.

Blocking of nozzles
Leaking from seat valves