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Chesterton Reliability Programs Bearing Life Extension. Proven Solutions to Improve Productivity and Lower Costs. Chesterton Bearing Reliability Program. Extend Bearing Life Increase Productivity Reduce Grease Consumption Reduce Operational Costs. Courtesy Bardon Bearing. - PowerPoint PPT Presentation
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CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 1
Proven Solutions to Improve Productivity and Lower Costs
Chesterton Reliability ProgramsBearing Life Extension
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 2
Chesterton Bearing Reliability Program
Extend Bearing Life
Increase Productivity
Reduce Grease Consumption
Reduce Operational Costs
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 3
Bearings Are Designed To Last ! SKF : Bearing life is designed to be 50,000 hours !
or 5.7 years of Continuous Service
Under Ideal conditions, bearings eventually fail from fatigue
Courtesy Timken BearingCourtesy Bardon Bearing
Bearing Life ( L10) is based on bearing design not environmental factors
<9% of Bearings Reach their L10 Design Life
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 4
General Relationships on Bearing Life
SPEED- Doubling Speed, cuts life in half. Halving speed increases life 2 X
LOAD- Doubling the load cuts life to 1/8 Halving load increases life by 8X for Ball Bearings, 10X for Roller Bearings
VIBRATION- Increase in vibration by 2X reduces Bearing life by 75%
MOISTURE- 200 ppm water reduces Bearing Life 48%
HARD CONTAMINANTS- Dust, Debris can result in immediate failure
FATIGUE – ONLY 9% Ultimate L10 Life Expectancy
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 5
Are You Satisfied with the Bearing Life in Your Plant?
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 6
Do your bearings survive under the following conditions?
Water/steam
High temperature/high speed
Heavy load/High pressure
Start/Stop/Standby Service
Rigorous environments
Corrosive Vapors
Food Sanitizers
Published Data can be used to Judge Grease Performance
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 7
80% of Bearing Failures are Lubrication Related
In Industry, Most Bearings Fail Due To Some Form of CORROSION, Accelerated by Heat, Load and Environment
Most Bearings Fail Early – Why?
Data courtesy of INA, FAG
B 20%
A 20%
C 15%
D 20%E 5% F 5%G 5%
I 10%
H <1%
aged lubricantA
unsuitable lubricantB
hard contaminants D
liquid contaminantsE
C poor lubrication 80%
mounting errorF
subsequent damagesG
material- and mfg defectsH
poor choice of bearings(design, size, load carrying capabilities)
I
20%
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 8
Performance Criteria and The Correct Grease
Property
Temperature Drop Point/Oil Separation
Extreme Pressure, Wear 4 Ball EP and Anti Wear
Speed Shear Resistance/Oil Separation
Moisture Water Washout
Corrosive Environment Corrosion Resistance/Salt Fog
Compatibility with existing grease Thickener Selection
Must First Determine the Operating Environment
Published Data can be used to Judge Grease Performance
OPTIMUM PERFORMANCE is a Result of Proper Selection of Base Oils, Thickeners, and Robust Additive Design…and Precise Manufacturing
Techniques
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 9
Test Criteria for Optimum Bearing Reliability
Grease Should Meet or Exceed All
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 10
You can see leakage OUT…But you cannot see Leakage IN
Chilled Water Pump
Conventional Lip Seals
CR (Mean Life 1844 hours)NATIONAL (Mean Life 645 hours)%
FA
ILU
RE
10
08
06
04
02
0
1000 2000 3000 4000TIME HOURS TO FAILURE
NATIONAL
CR
Percent Failure vs. Hours to Leakage
Lip Seals Protect for < 3000 hrs, BUT bearings are designed for 50,000 hrs !
Lip Seals are Used to Protect 95% of Rotary Shaft Bearings
Keep Lubricant IN and try to Keep Water Out !
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 11
How Much Moisture is TOO MUCH?
Ref. SKF
Water Reacts To Steel Bearings Rust, Corrode And PitTo Protect, The Grease Must Passivate The Bearing With Active, Corrosion
Inhibitors And Functional Additives
0.01% = 100 ppm
0.05% = 500 ppm
0.10% = 1.000 ppm
0.15% = 1.500 ppm
0.25% = 2.500 ppm
0.50% = 5.000 ppm
1.00% = 10.000 ppm
The Effect of Water in Oil on the Bearing Life
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 12
Effects of Corrosion The Primary Challenge to Bearings in
Industry
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 13
The Facts of Unsatisfactory Bearing Life We Have To Deal With…
95% of All Rotary Shaft Bearing 95% of All Rotary Shaft Bearing
are protected with Elastomeric Lip Seals !are protected with Elastomeric Lip Seals !
Bearings Are Designed To Last !Bearings Are Designed To Last !SKF : they have a design life of 50.000 hours ! SKF : they have a design life of 50.000 hours !
Effective life is less than 3000 hours! Effective life is less than 3000 hours! They damage shaft / allow oil to leak out and Environment leak in!
Almost 90% of the Bearings fail ….. …. they do NOT reach the design life !80 % of premature bearing failure are caused by faulty lubrication and/or contamination !
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 14
Attack the Root Causes and Maximize Bearing Life !
THE FINAL Protection to the Bearing is the Lubricant…The Root Cause of Poor Bearing Life is NOT
LUBRICATION PRACTICES or Poor MAINTENANCE
but Using Lubricants that are Deficient in PREVENTING CORROSION, WEAR, and PITTING.
STOP CORROSION…INCREASE BEARING LIFE…
IMPROVE MTBR…SAVE MONEY
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 15
Grease Tests - Corrosion Resistance
1000 hours ASTM B117
ASTM B117
Typical Grease - 50 hrs
615 “family” -1000 hrs
5% Salt Water, 35OC
ASTM B 117 Salt Fog Test
After 48 hours
615 HTGLi Cplx, synthetic
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 16
Corrosion ProtectionSalt Fog Performance - ASTM B117
1000 hours ASTM B117
0 200 400 600 800 1000 1200
# 615 Family
AluminumComplex
LithiumComplex
Hours to Failure
12 microns
37 microns
Film Thickness
20x Better
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 17
Chesterton QBT™ Additive Plating Technology
QBT™ smoothes out surface roughness, reduces wear and vibration.
This molecular surface chemistry passivates the steel and extends bearing life by reactively fusing a “wear shield” onto the contact surfaces. Micro porosity is “filled in” and reactive Fe++ ions are inhibited.
QBT™ works even in the presence of up to 30% water contamination.
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 18
Chesterton QBT Grease Family
Very High Dropping Point, 300oC ( 570
oF)
Temperature Range - 40oC to 204
oC (- 40
oF to 400
oF)
Excellent Shear Resistance, Virtually No Thinning
Resists Oxidation, Ozone Degradation
Excellent Shock Load and Wear Properties, 4 Ball Weld Load, 620 to 800Kg
Very High Timken O.K. Load 29 kg (65 lbs.)
Good Compatibility with Popular Greases
Very High Water Washout Resistance, Below 0.05%
Extreme Water Tolerance (Add 30% Water and Still Get 20 kg (45 lbs.) Timken)
Excellent Corrosion Resistance, 1000 Hrs Salt Fog Test
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 19
Grease Compatibility
613 615 622 625 629 630 633 635
Aluminum Complex I A C A I A A A
Barium Complex I C I C C C C C
Calcium Stearate A C I C I C C C
Calcium 12 Hydroxy C A C A A A A A
Calcium Complex I I I I C I I I
Calcium Sulfonate A C A C I C C C
Clay Non-soap I I I I A I I I
Lithium Stearate C A I A I A A A
Lithium 12 Hydroxy C A I A I A A A
Lithium Complex C C C C I C C C
Polyurea, Conventional I I I I I I I I
Polyurea, Shear Stable C C C C I C C C
C = Compatible. Grease may be installed directlyA = Acceptable. 10% Reduction in Consistency. Grease normally, observe 24 Hrs. Re-grease if oil bleedI = Incompatible. Old grease must be removed from lines and bearing housing
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 20
Industrial Grease Program
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 21
Food Grade Grease Program
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 22
Critical Lubricant Performance Tests
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 23
Grease must be stable and not thin out…Shear Stability, ASTM D217Change in Penetration after Shear
Measured in units of 0,1 mm (4 mil)
Grease Penetration Measured after 60, 10,000 and 100,000 strokes.
A grease may “thins” with shear – higher penetration.
Key aspect is to use low shear thinning greases to maintain NLGI in service
Typical grease 7-10% change or 20-35 units on penetration scale.
BE CAREFUL NOT TO CHANGE NLGI in SERVICE
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 24
…and oil NOT separate, even in storage.
Oil Separation, ASTM D1742
Measures % oil that separates to the top of the grease after heat aging.
Typical grease 1 to 8%
615 “family” 0 to 0.2%
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 25
Calcium
Clay
Lithium
Aluminum
Complex
Polyurea
Calcium
Sulfonate
Synthetic
Polymer
Temperature Range, oC-40 0 40 80 120 160 200 240
-18o to 138oC (- 0.4 º to 280 º F)
-23o to 93oC (-9º to 199º F)
-34o to 177oC (- 29 º to 350 º F)
-34o to 204oC (- 29 º to 399 º F)
- 40o to 204oC (- 40º to 399º F)
-23o to 177oC (9º to 350º F)
-23o to 170oC (- 10 º to 338 º F)
Useful Temperature Limit is a Function of Shear and Oxidative Stability, Not
Dropping Point
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 26
A. ASTM D2596 4-ball EP
Maximum load, before seizure, kg
1200 rpm
Typical Grease 250kg
“615 Family” 620 to 800kg
1 hour 1200 rpm, at 40 kg, ave. scar in mm
Typical Grease 0.5 to 0.7 mm
615 “family” 0.40 mm
B. ASTM D2266 4-ball Scar Diameter, mm
Ability to Take Load and Prevent Wear 4-Ball Grease Tests
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 27
Water Washout Resistance ASTM D1264 (DIN 51807)
Typical Water Resistant Grease 3 to 5% Exceptional 1-2% 629 < 0.2% 25 x Better 615 and QBT Family - 0.05% 100 x Better
Water, 80oC (175oF)
Grease Packed Bearings
Water Reacts To Steel. Bearings Rust, Corrode And PitTo Protect, The Grease Must Passivate The Bearing With Active, Corrosion Inhibitors And
Functional Additives
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 28
Short Term Corrosion Resistance TestsMany “mild” ASTM corrosion tests reported,
D130 – Copper Strip Tarnish Test
D1748 – Rust Protection in Humidity Cabinet
D4627 – Iron Chip Corrosion Test
D6138 – “Emcor Test’, 30 days, sealed bearings
EMCOR Humidity Cabinet Copper Strip Test
Standard Grease Corrosion Test Methods are Short Duration, Non Aggressive Exposures. Virtually any grease will “PASS” the test. However, the real world test
of Industrial Exposure produces different results.
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 29
Photos of Types of Bearing Failure
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 30
Types of Corrosion
Chemical
Galvanic
Localized Pitting
Embrittlement
Intergranular
Yellow Metal
High Temperature Oxidation
Abrasive Corrosion
Required Conditions
– Oxygen
– Moisture
Accelerants for Corrosion
– Salts
– Chemicals
– Temperature
– Environment
– Dissimilar Metals
Water Reacts with Steel Bearings to Rust, Corrode And PitTo Protect, The Grease Must Passivate The Bearing With Active, Corrosion Inhibitors And
Functional Additives
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 31
Bearing Corrosion is a Failure of the Grease Film to Protect
The grease is the last line of bearing protection
For reliable performance the grease must have Extremely low water washout Excellent corrosion inhibition Maintain a high lubricating film even when contaminated with water
Moisture / Water – cause multiple types of corrosion
1. Low levels, ppm – condensation, lip seal leakage Result - hydrogen embrittlement , pitting, “watermarks”,
“black oxide”
2. Higher levels – Grease washout Grease thinning, no film strength, bearing scars, cage
wear Aggressive rusting of the carbon steel bearing, “red
oxide”
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 32
“Watermarks”
Black oxide
“Speckling”
Common Examples of Corrosion-Pitting, Fretting, Wear !
Wear
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 33
Common Examples of Corrosion-Pitting, Fretting, Wear !
Fretting
Hydrogen Imbrittlement
Yellow Metal staining
Abrasion Corrosion
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 34
QBT Described and Vibration Analysis
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 35
Chesterton QBT™ – Technology Overview
Chesterton's QBT™ Grease Family is formulated using a surplus of Lubricity, EP and Anti-Wear additives, blended into a highly refined base oil, and thickened with a metallic organo-sulfonate complex. The resulting grease is "Best in Class" with respect to EP, Lubricity, Corrosion & Water Resistance.
Unlike conventional Aluminum, Calcium, & Lithium soap and complexed thickeners, Chesterton QBT™ based greases are immune to hydrolysis or water breakdown. The grease remains functional even in heavy water contaminated bearings and equipment.
QBT™ (Quiet Bearing Technology) uses state of the art tribological technology to reduce vibration and ultra-sonic bearing noise. Proprietary polar and non-polar additives and thickener chemically fuse to the metal surfaces filling in asperities to form a "wear shield" on the metal surfaces.
This fusion of lubricating additives and thickeners to the molecular surface of the metal, protects the bearings from
WEAR, PRESSURE and WATER CORROSION.
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 36
615 HTG –QBT™Additives at Work Dryer Fan, Horizontal Bearing, Paper Mill
10.000
7.500
5.000
2.500
20/10/99 14/11/99 09/12/99 03/01/00 28/01/00
Vib
ratio
n,
Kh
z
615 HTG with new bearing
MPM Multiparamater Receiver, Wilcoxon Model 782A Sensor
Alarm@4.0Khz
Acceptable@3.0Khz
Li Cpx with new bearing
Vibration Analysis> 300% Increase in MTBR
CHESTERTON
© Copyright 2009 A.W. Chesterton, All rights Reserved 37
615 HTG Family with QBT™
Industrial
615 HTG #2,
615 HTG #1,
635 SXC, Synthetic, Extreme Pressure, Corrosion Resistant Grease
633 SXCM, Synthetic, Extreme Pressure, Corrosion Resistant Grease with Moly
Food Pharmaceutical, H1
625 CXF, Corrosion Resistant, Extreme Pressure, Food Grade Grease
630 SXCF, Synthetic, Ext. Pressure, Corrosion Resistant Food Grade Grease
Extreme Pressure (EP) - 620 to 800kg vs. 250kg for typical greases
Water Washout – as low as 0.05%, vs. 8% for typical lithium based grease
Corrosion Protection – 1000 hours vs. 50 hours in ASTM B117 salt fog test.
Unique Combination of Performance
Recommended