Petroliance 12 2008
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Piedmont Chapter 14,
Vibration Institute Meeting
December 5, 2008
Midlands Technical College
West Columbia, SC
Introduction and Timing
Jeremiah JB Bacon C.L.S.
PetroLiance, LLC
Presentation should take about 1 hour.
What is Contamination?
ANY FOREIGN MATERIAL THAT
ADVERSILY AFFECTS THE
OPERATION OF YOUR EQUIPMENT.
Wrong Oil
Chemical
According to Vickers...
The ROOT Cause of
UP TO 80 %
of Hydraulic Failures
Are caused by
CONTAMINATION
It Effects All Forms of Equipment....
1
SKF Quote
Under special operating
conditions, bearings can attain
a much longer life than
predicted by normal life
calculation methods. These
special conditions are when the
rolling surfaces are
effectively separated by a
lubricant film and when the
surface damage caused by
contaminants is limited.
limited In
fact, under ideal conditions, it
is possible to speak of infinite
life.
2
Vickers Quote
Proper selection and placement
of contamination control devices
in a system to attain the
targeted cleanliness eliminates
(the root cause of) up to 80%
of hydraulic system failures.
1 SKF Bearing Maintenance Handbook
2 Vickers Guide to Systemic
Contamination Control
Why Is Cleanliness So Important?
Typical bearing application
Oil Thickness is
0.1 to 3 Microns
h
Lubricant
Load Zone Pressures Can Be
Greater Than 100,000 PSI
Contamination Destroys Equipment
3 Micron
Particle
Abrasive Wear is the most common type of wear.
The Life of a Typical Hydraulic Pump
The life of a typical hydraulic pump can be
predicted based on the amount of contamination
that passes through the pump during its life.
50 gpm Pump
ISO 21/18
1750 lbs/Yr
2 Yr. Pump Life
ISO 14/11
50 lbs/Yr
>14 Yr.Pump Life
What Size Particles Are We Talking About?
What size particle
can you see?
Table Salt 100 µ
Human Hair 70µ
Lower Limit of site
~ 40 µ
Flour 25 µ
White Blood Cell
25 µ
Red Blood Cell 8 µ
Wh a t Si ze Pa r t i c l e Wi l l
Ca u s e A Pr o b l e m ?
1 Micron = .000039 INCH
15 µ
1µ
Contamination in a Hydraulic Piston Pump
What does it do?
The abrasive wear from the
particulate damages the
swashplate, piston shoe,
piston, cylinder wall,
cylinder block and valve
plate.
Particulate can clog the
piston shoe opening.
Contamination in a Servo Valve
What does it do?
The valve spools can have 1 micron clearances.
Particulate will damage the spool and cause
actuation problems due to internal leakage.
Abrasive Particulate Effects In Gears
Abrasive particles cause seals to erode
and bearings to wear prematurely.
Shortens Rebuild/Replace Intervals
Increases Oil Consumption from Leaks
Increases Maintenance Costs
Water Is Harmful Too!
Water is the SECOND
Most Destructive
Contaminant!!!
Changes Oil Viscosity
Rust & Corrosion
Hydrogen Embrittlement
Acids
Pitting
Causes Foaming
Sludge & Sediment
What Water Contamination Can Do to a
Bearing
The Problem: Water causes Hydrogen
Embrittlement of the metal and premature fatigue.
Hydrogen
Embrittlement
Spalling from
Embrittlement
Water, What is ok?
ACCEPTABLE
LEVELS: Typically
below 250 PPM.
It is normal to see
levels of 150 to 250
PPM or 0.015
0.025 % in SC
You can see water
at around 900 PPM
If We Can t See it,
How Do We Know It s There?
Heat
Vibration
Equipment Failures
Sludge
Cloudy Oil
Residue
Sticking Valves
Premature Failures which
equates to Production Loss & Money
All ending up in
If We Can t See it,
How Do We Know It s There?
Use Oil Analysis with Particle Counts.
ISO Particle Counts
It is important to understand what ISO
Particle Counts are.
What is it?
Quantitative analysis of oil to determine the
distribution of particle sizes in the oil
Why?
Try to keep oil at a cleanliness level to prevent
wear and failures.
Targeted to remove clearance size particles out
of the oil
Filter Patch: ISO Rating of 20/17/15
Range or code
Greater Than 4 micron
Greater Than 6 micron
Greater Than 14 micron
We have to have some
way of knowing it is
there....
Oil Analysis ISO
Particle Counts
Cleanliness Code 20/17/15
Filter Pad PC Scale:1Division =14 m
ISO Code Range Counts
ISO Cleanliness
Code 20/19/16
ISO Cleanliness Comparison
OEM Recommended ISO Codes
What is acceptable?
There are definite
standards set by
each company.
Here are some good
examples.
How Do We Control Contamination?
To control contamination, you ll need to assess just
how contaminated your systems are.
Use Oil Analysis with Particle Counts to determine
current system cleanliness levels.
Identify the most sensitive components on each
system.
Set system cleanliness goals base on those
sensitive components identified.
Document ISO cleanliness code and water content
results for each system.
How Do We Control Contamination?
Once you have established how
contaminated your systems are, and what
cleanliness level your system should be to
maximize life;
Initiate a directive to work toward those goals by
putting best practices in place.
Once your cleanliness goals are met, develop a
maintenance plan to keep systems clean.
