Why Bearings Fail

8/2/2019 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

[email protected]

[email protected]


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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.

Why Bearings Fail

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