There are three
principal methods to measure the contamination level in a component, circuit,
or system. The methods are Gravimetric Measurement (ISO
4405); Particle Size Distribution Analysis (ISO 4406 or NAS 1638); Maximum
Particle Size Analysis (ISO 4407).
Maximum
Particle Size Analysis (ISO
4407)
This evaluation
is done using a microscope. A microscope is used to identify and measure the size of individual pieces of
contaminant. Particle size is important in reference to maximum clearances of hydraulic
components.
Whether
hydraulic assembly cleanliness applies to you or not, it is worthwhile to
understand the significant impact that contamination levels can have on the
life of hydraulic system components.
Implementing a thorough cleanliness system
may have a significant impact on warranty returns for hydraulically powered equipment.
