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This trend can be compared to the growth of particle contami-
nation in machinery. Particles produce particles. In fact, one
particle can generate as many as 20 new particles within a machine.
Of course, this will depend on many variables, such as particle
ingression rates, the fi ltration rate, the likelihood of wear genera-
tion, etc. Regardless, when particles are the instigator of new
particles being created, the contamination can quickly escalate.
By adding quarterly sampling dates and ISO particle contami-
nation codes to Figure 1, we can illustrate a lubricated machine
that was accidentally introduced to new contaminants and
resulted in increased wear generation. Note the dramatic trend
toward the most recent dates in Figure 2. When this type of
growth in particle concentration occurs, it will be linked to an
imminent machine failure.
In order to predict an impending rapid growth of particle
contamination, oil sampling must be performed frequently enough
to detect a slight uncharacteristic increase. For example, in Figure
1, if the world population is measured every 1,000 years, the results
would be 0.1 billion, 0.1 billion, 0.1 billion, 0.2 billion, 0.2 billion
and fi nally 7 billion. However, if the population is measured twice
as frequently or more, it would be much easier to recognize the
start of the abnormal increase. Sampling machines for changing oil
conditions is no different.
About the Author
Bennett Fitch is a technical consultant with Noria Corporation. He
is a mechanical engineer who holds a Machine Lubricant Analyst (ML A)
Level III certifi cation and a Machine Lubrication Technician (MLT) Level
II certifi cation through the International Council for Machinery Lubrica-
tion (ICML). Contact Bennett at bfi tch@noria.com.
Quality trending
provides a powerful
means of recognizing
when an oil property is
moving in an unhealthy
or threatening direction.
8000
B.C.
4000
B.C.
3000
B.C.
2000
B.C.
1000
B.C.
0
1000
A.D.
2000
A.D.
0
1
2
3
4
5
6
Apr-13
Jul-13
Oct-13
Jan-14 Apr-14
July-14
Oct-14
Jan-15
14/11
15/12
16/13
17/14
18/15
19/16
21/18
FIGURE 1. The world's population growth
FIGURE 2. An illustration of particle contamination within a machine
Industrial
Revolution
The Plague
