October 30, 2007 © SKF Group Slide 1

Low Friction / Energy Efficient Rolling Bearings

Presentation to : TAPPSA Members

Date : 23 September 2010

Presenter : Greg Sassen

Application Engineer – SKF South Africa

October 30, 2007 © SKF Group Slide 3

Agenda

•Introduction

•SKF E2 Energy Efficient Deep Groove Ball Bearings

•Energy Efficient Fan Bearing Solution

•General discussion

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• Energy consumption is projected to grow by 50% over the 2005 to 2030 period.

• Energy demand to increase by 85% for Non-Organisation For Economic Co-operation and development (OECD) countries.

• Energy demand to increase by 19% in OECD countries.

Global energy trends – International Energy Outlook (IEO2008) projections

World Market Energy Consumption forecast 2005-2030

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History of rolling bearing development

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Rolling friction versus sliding friction?

Rolling bearings - rolling friction

Plain bearings -sliding friction

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Reduced power loss and total cost of ownership

• Energy cost is 95% of total cost of ownership of electrical motor

• Using Energy Efficient deep groove ball bearings

• Reduces energy consumption, thus energy bill

• Contributes to increase the electrical motor efficiency

• Anticipates the future e-motor efficiency legislations worldwide

• Provides longer bearing service life

Cost of ownership distributionof an electrical motor over 10 years

EnergyMaintenancePurchasing

95%

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Benefits of energy efficient rolling bearings

Less frictionHigher

Reference speed

Longer relubrication intervals

Less power consumption

Lower operating temperature

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SKF Energy Efficient (E2) deep groove ball bearings

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Test conditions:•SKF E2. versus SKF standard

•6203-2Z size

•Radial load: 120N

•Friction torque: value after 24h

•3 speeds in rpm: (2000, 4000, 16000)

•Testing Temperature on OD: 30 °C

Friction torque test on SKF AV1-RIG

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Test results – E2.6203-2Z/C3 on SKF AV1 Rig

66

45

30

010

20

3040

50

60

7080

90

100

2000 rpm 4000 rpm 16000 rpm

Standard bearing

E2 Bearing

Energy savingsFr

icti

on t

orq

ue a

nd e

nerg

y

consu

mpti

on

Speed

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Friction Torque test overview

Test conditions:•SKF E2 design versus SKF standard

•6306 size

•2 load cases: C/P=10 & C/P=15

•3 temperatures (70/85/100°C)

•3 speeds in rpm

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Lower friction torques for SKF E2.6206-2Z/C3 Energy Efficient Bearings

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Service Life test results – SKF ROF tests

SKF E2 Energy Efficient bearings have been subjected to SKF ROF service life tests.

Test conditions:• Test temperature - 150°C

• Reference size - 6203

• Speed - 10000 rpm (285 000 ndm)

0

1

2

3

service lif e

Standard

Energy Effi cient

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Fan energy consumption

• Fans are consuming 20% of industrial world energy

That’s equivalent with the energy consumption of

150 million houses or 470 nuclear power plant reactors

• From a Life Cycle Cost perspective, up to 90% of the total cost of the fan is energy

Energy 89% Maintenace 8% Investment 3%

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Typical fan bearing arrangement

Non-LocatedBearing

LocatedBearing

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Evolution of spherical roller bearing performance

Mass (kg)

Explorer

22322 22320 C 22318 CC/W33 22317 E 22315 E

18,1

12,8

8,67,2

5,2

1962

1981

1989

1950

1999

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The E2 spherical roller bearing solution

+

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How the E2 solution was achieved

Bearing•Decreased number of rollers

•Optimised surface finish on bearing raceways and rolling elements

•Optimised rolling element and raceway profiles.

•Fewer cage pockets

•Manganese phosphated cage pocket surfaces

Lubricant•Specialised SKF LESA 2 grease

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Cross location – Housing bore too small or oval

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Outer ring creep caused by unbalance

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SKF Fan Solution

SKF ExplorerCARB

Non-located bearing

Located bearing

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Self aligning bearing solutionCompact Aligning Roller Bearing

(CARB)• CARB guarantees frictionless axial

movement

• No possibility to create internal axial forces

• Load is always distributed evenly

• Stress is minimized and bearing function improved

Fr

Fa=0

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Potential applications for energy efficient bearings

•Electric motors

•Fans & blowers

•Conveyor idler rollers

•Pumps

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Questions?