Why Bearings Fail
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CHESTERTON
CAUSES OF BEARING FAILURE Improper Lubrication - 43%
How Much, How Often, What Type, What Thickness,
What Properties are Important
Improper Mounting - 27% Alignment, Work Area, General Practices, Inventory
Control and Storage of Bearings
Other Lubrication Causes - 21% Separation in Storage
Temperature Limit Exceeded
Moisture Contamination
Other Contamination
Fatigue - 9% Ultimate L10 Life Expectancy
64% of Bearing Failures are Lubrication Related ISNot The Whole Story
In the Industry We Serve, Most Bearings Fail Due ToSome Form of CORROSION
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CHESTERTON
INDUSTRIES SERVED
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CHESTERTON
INDUSTRIES SERVED
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CHESTERTON
EFFECT OF MOISTURE ON BEARINGLIFE
MOBIL OIL REPRINT
Base Oil DescriptionWater Content of
Wet Oil, %
Fatigue Life
Reduction,
Percent
Test Equipment Author Reference
Mineral Oil -Dried 0.002 48
0.014 54 4-Ball Scott, 1960
3.00 786.00 83
Squalene Oil 1.000 32-43 4-Ball Schatzberg & Felsen, 1969
Mineral Oil-Dried
Not Stated,
Moist
environment
80 4-Ball Ciruna & Szieleit, 1972
Esters 0.050 29-73 #204 Bearings Fein, 1969
Mineral Oil-Based
Hydraulic Oil1.00 45
Angular Contact
BearingsFelsen,1972
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CHESTERTON
WATER WASHOUT RESISTANCEASTM D1264 (DIN 51807)
% Weight Loss of Grease Measured Typical Grease (Lithium) - 5%
Water Resistant Grease
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90
80
70
60
50
40
30
20
10
0.002 3.0 6.0
% WATER IN OIL
%R
EDUCTIONIN
FATIGUELIFE
48
7883
Mobil Oil evaluation on bearing fatigue life
0.002% water reduces fatigue life 48%
6.0% water reduces fatigue life 83% 0.002% water is 1 drop of water in a quart of oil
WATER CONTAMINATIONREDUCES BEARING LIFE SIGNIF ICANTLY
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CHESTERTON
^30K^
Contacts Here
FRETTED SHAFTS & SLEEVES When shaft scoring occurs. A
newly installed Lip Seal ridingin same location on shaft willleak.
Water penetrates the bearing
immediatelyin all cases
corrosion is RAPID and BearingLife is reduced
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CHESTERTON
^30K^
Contacts Here
Fretted Shafts & Sleeves When shaft scoring occurs. A
newly installed Lip Seal ridingin same location on shaft willleak. A SpediSleve Seal isoften used.
While an improvement, the sealeventually fails, waterpenetrates the bearingimmediatelyin all cases
corrosion is RAPID and BearingLife is reduced
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CHESTERTON
^30K^
Contacts Here
Numerous Self-Fretting Bearing Seals Available
Some are just metallic
shields as OEM
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CHESTERTON
CIC 7810-192Exhibit III
%F
AILURE
100
80
60
40
20
1000 2000 3000 4000
TIME HOURS TO FAILURE
NATIONAL
CR
CR (Mean Life 1844 hours)
NATIONAL (Mean Life 645 hours)
CIC 7810-192Exhibit IV
NATIONAL
Hours to Failure
MEDIAN RANK
( % Failure)CR WAVESEAL
Hours to Failure.
182
188
275
300
556
648
772
902
1264
1366
6.7
16.32
25.94
35.57
45.19
54.81
64.43
74.06
83.68
93.30
144
576
1343
1736
1763
1973
1979
2946
2982
3003
REPRINT FROM A CR INDUSTRIES REPORT
Percent Failure vs. Hours to Leakage
Conventional Bearing Lip SealsTesting Data
(57 Days) (125 Days)
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CHESTERTON
CORROSION PROTECTIONSalt Fog Performance - ASTM B117
0 200 400 600 800 1000 1200
# 615 HTG
Aluminum
Complex
Lithium
Complex
Hours to Failure
12 microns
37 microns
Film Thickness
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CHESTERTON
BALL AND ROLLER BEARING LUBRICATION(OIL AND GREASES)
Shaft Diameter
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CHESTERTON
BALL AND ROLLER BEARING LUBRICATION(OIL AND GREASES)
Shaft Diameter
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CHESTERTON
615 HIGH TEMPERATURE GREASE Very High Dropping Point, 300
oC ( 570
oF)
Temperature Range - 40o
C to 204o
C (- 40o
F to 400o
F)
Excellent Shear Resistance
Excellent Shock Load and Wear Properties
Very High Timken O.K. Load 29 kg (65 lbs.)
Good Compatibility with Popular Greases
Very High Water Washout Resistance, Below 1.6% Loss
Extreme Water Tolerance (Add 30% Water and Still Get
20 kg (45 lbs.) Timken)
Excellent Corrosion Resistance
Highest Rating Possible for Automotive Bearing and
Chassis Lubrication, NLGI GC-LB
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CHESTERTON
615 HTG #1 Best in Class Extreme Pressure Properties and
Antiwear Characteristics
Exceptional Corrosion Protection
Excellent Oxidation Resistance, Long Grease Life
Excellent Resistance to Water Washout andContamination
Easily Pumpable, Good in Central Lubrication Systems
Shear Stability and Grease Performance Maintained
Over Wide Temperature Range Measurably Longer Bearing Life
Temperature Range - 40oC to 204
oC (- 40
oF to 400
oF)
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CHESTERTON
615 HTG #1General Rule of Thumb on Where to Use
615 # 1 Vs. the Standard 615:
Where Operating Speeds are Higher
Where Average Operating Temperatures are Lower
When Customer Wants to Use in Automatic LubricationSystem
See Pocket Guide for Reference on Specific Operating Conditions
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CHESTERTON
TEMPERATUREEFFECT ON GREASE LIFETIME
Most Mineral-Oil-Based Greases (of Adequate Dropping Point)
Will Operate Successfully to About 121oC (250
oF).
A Smaller Number Can Handle 150oC (300
oF). A Few Mineral-
Oil-Based Greases Can Operate to About 177
o
C (350
o
F).
Relubrication Intervals - Rolling Element Bearings, 8 hours per Day
82oC (180
oF) - 6 Months
104oC (220
oF) - 3 Months
149o
C (300o
F) - 1 Month193
oC (380
oF) - 1 Week
238oC (460
oF) - 1 Day
Source: NLGI, Lubricating Grease Guide
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CHESTERTON
LUBRI-CUP Demand Feed System -
Patented Metering System, Slowly
Feeds Grease Only as Needed Prevents Over or Under Filling of
Bearings
Eliminates Cause of Over 40% ofBearing Failures
Low Feed Pressure PreventsBearing Seal Failure
Time Interval for RelubricationIncreased by 6x
Reduces Labor Cost to Regrease byOver 80%
Can Be Mounted at Any Angle Transparent Grease Reservoir -
Easy to See Grease Level
Easy to Refill in Place
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CHESTERTON
REFILLING THE LUBRI-CUP
Refilling Lubri-Cup with 615
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CHESTERTON
BEARING LIFE EXTENSION withLUBRICUP and 615 GREASE
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CHESTERTON
615 HTG Vibration AnalysisDryer Fan, Horizontal Bearing, Paper Mill
10.000
7.500
5.000
2.5000
20/10/99 14/11/99 09/12/99 03/01/00 28/01/00
Vibration,K
hz
615 HTG APPLIED
MPM Multiparamater Receiver, Wilcoxon Model 782A Sensor
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CHESTERTON
615 Additive Plating Technology
615 smoothes out
surface roughness,reduces wear andvibration. Extendsbearing life.
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CHESTERTON
615 Additive Plating Technology
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CHESTERTON
615 HTG Technology Overview
Chesterton's 615 is formulated using a surplus of Lubricity, EP and Anti-Wear additives,blended into a highly refined G III 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 615 is immune to hydrolysis or water breakdown. The grease remainsfunctional even in heavy water contaminated bearings and equipment.
Chesterton's 615, with QBT (Quiet Bearing Technology)uses state of the arttribological technology to reduce vibration and ultra-sonic bearing noise. Proprietarypolar and non-polar additives and thickener chemically fuse to the metal surfaces fillingin asperities to form a "wear shield" on the metal surfaces.
This fusion of lubricating additives and thickenersto the molecular surface of the metal, protects the bearings from
WEAR, PRESSURE and WATER CORROSION.