TABLE OF CONTENTS Solid contamination can be generated by many events so that high contamination levels at a given point in a machine can be used as a signal that something is abnormal.
It could be caused by a failed filter, in which case two samples, taken upstream and downstream of the filter, can prove the failure. (That argues for installing sampling points on either side of the filter and monitoring just downstream on a regular basis. A high particle count will be followed by a sample from each side of the filter.)
An increased wear rate in the wearing parts of the machine can increase the number (and size) of the particles present.
Contamination can enter the system through a breather pipe, or through faulty seals, or because a protective filler cap was not replaced.
When the oil becomes acidic or highly oxidized, it can attack the metallic components in the oil wetted path and generate a great deal of corrosive sediment.
These are but a few of the sources of solid contaminants. Spectroscopy will give a good indication of the elemental concentration of any debris present, provided that the material is not organic in nature. The most common form of contamination is moisture. This has many effects, including the aiding of acidity formation and lack of lubrication. The major tests for both particle contamination and moisture will be addressed here.
Particle Count (PC). A method used to count and classify particulate in a fluid according...
