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OIL ANALYSIS
Take this modest motor-coupling-pump skid assembly:
As a system, it can be re-shown as a block diagram, such as this RBD
(values shown as an example only):
Node 1
Block 1 Block 2 Block 3
Node 2
0.97 0.99 0.90
With an overall system reliability of 0.864 or 86.4%
Do you recall our oiler, Leroy? And do you recall I took some literary
license and made reliability, probability, chances and odds synonymous?
Here is the payoff.
What I'm reprinting here is the exact text from an actual PM work
order — this is from a multi-billion-dollar company:
"Apply 4 grams of grease to the bearing."
For Leroy, the system he just entered reads in his mind like this,
"Leroy, get a grease gun, go to the press, locate the bearing grease fitting,
shoot in 4 grams of grease, document that activity (optional — as
usual), put the grease gun away."
Or,
R1 X R2 X R3 X R4 X R5 X R6
For us to ponder:
R1 = Which grease gun? Which grease? How clean is it? Does it have
the right additives?
R2 = Which press?
R3 = Which grease fitting? Is there a grease line, or is it direct applica-
tion?
R4 = How much really is 4 grams? Is the grease gun calibrated? How
do we know how much one pump puts out?
R5 = Document what, the number of grams, the number of strokes, the
type of grease and the condition of the bearing?
R6 = Where do I put the grease gun, on the back of my cart, in my tool
box or back in the crib?
To easily make the calculation of Leroy's work, which is a system of
related activities, let's agree to use the U.S. Department of Education's
