Contribution of Viscosity Modifiers on Fuel Economy Engine Oils

KSTLE Lubricants Symposium 2007

Cheju, 13 - 14 September

Dr. Hitoshi Hamaguchi

Degussa Japan Co., Ltd.

KSTLE Lubricants Symposium 2007

Cheju, 13 - 14 September

Dr. Hitoshi Hamaguchi

Degussa Japan Co., Ltd.

Agenda

1. Fuel Economy Regulations

2. Vehicle Fuel Economy

3. Engine Oil and Fuel Economy

4. Ultra Low Viscosity Engine Oil

5. Influences of Viscosity Modifiers on Fuel Economy

6. Summary

Fuel Economy Regulations

USA

• CAFE (Corporate Average Fuel Economy) (mpg)

Model Year 2008 2009 2010 2011

Passenger Car 27.5 27.5 27.5 27.5

Light Truck 22.7 23.4 23.7 24.0

Europe

• Agreement between EU and ACEA

– 25% reduction in CO2 emission (Year 1995 vs. 2008)

• Proposed target by EU Comission

– 35% reduction in CO2 emission (Year 1995 vs. 2012)

Fuel Economy Regulations (continued)

Japan

• Fuel economy target by Energy Conservation Law (1998) [10.15 mode]

• Draft fuel economy target by Energy Conservation Law (2007) [JC08 mode]

• Fuel economy target for heavy duty trucks (2006)– 12.2% improvement in average fuel economy (Year 2002 vs. 2015)

Type of Vehicle 1995 actual FE 2010 target FE Improvement

Passenger Cars 12.3 Km/L 15.1 Km/L 22.8 %

Trucks with GVW < 2.5tons 14.4 Km/L 16.3 Km/L 13.2 %

Type of Vehicle 2004 actual FE 2015 target FE Improvement

Passenger Cars 13.6 Km/L 16.8 Km/L 23.5 %

Light Buses 8.3 Km/L 8.9 Km/L 7.2 %

Light Trucks 13.5 Km/L 15.2 Km/L 12.6 %

CO2 Emissions by Sector in Japan (Fiscal 2004)

Residential13.0%

Commercial17.6%

Transport20.4%

Others6.7%

Industries36.3%

Energy Industries6.0%

Total CO2 Emissions1,279 million

tons

CO2 Emissions by Sector in Japan (Fiscal 2004)

Engine Technologies

Improvement in thermal efficiency Lean-burn Direct injection Variable mechanism (variable cylinder, VVT, etc.)

Reduction of friction loss Piston & ring friction reduction Low friction engine oil Variable auxiliary drive

Leading Fuel Economy Vehicle Technologies

Improved Aerodynamics(reduced resistance to airflow)

Improved body configuration

Reduction of Vehicle Weight

Expanded use of lightweight materialsImproved body structure

Improved Drive System

Expansion of lockup areaExpanded number of transmission gearsCVT

Reduction of Roll Resistance

Low roll-resistance tires

Other

Electrical power steeringIdling preventionHybridization

Source: JAMASource: JAMA

Concept of Low Friction Engine Oil

Lower Friction• Reduce friction loss under boundary lubrication regime

Lower Viscosity• Reduce churning loss under hydrodynamic lubrication regime

Higher Viscosity Index• Reduce churning loss under low temperature condition• Reduce boundary friction under high temperature condition

Concept of Low Friction Engine Oilon the Streibeck Curve

Fri

ctio

n

Speed x ViscosityLoad

BoundaryLubrication

EHL Hydrodynamic Lubrication

Friction Reduction

by Better Low

Temperature Fluidity

Friction Reduction by FM

Friction Reduction

by Lower Viscosity

SGSG11

22

33

44

55

Seq

.VI

F/E

im

pro

vem

ent

Seq

.VI

F/E

im

pro

vem

ent

, %

(vs

. 20

W-3

0),

% (

vs.

20W

-30)

GF-1GF-1 GF-2GF-2

00

11

22

33

Seq

.VIB

F/E

imp

rovem

ent

Seq

.VIB

F/E

imp

rovem

ent

, % (vs. 5W

-30), %

(vs. 5W-30)GF-3GF-310W-3010W-30

5W-305W-30& 0W-30& 0W-30

5W-205W-20

& & 0W-200W-20

19901990 200520052000200019951995

GF-GF-４４

20102010

GF-5GF-5

Source: K. Nakamura, Nissan MotorsSource: K. Nakamura, Nissan Motors

Trend in Fuel Economy Requirement(ILSAC Specifications)

Japan

5W-405%

10W-3040%

5W-3030%

0W-301%

5W-205%

0W-2010%

15W-504%10W-40

5%

PCMO Viscosity Grade in Japan (2006)

Source: SAE Asia Market SurveySource: SAE Asia Market Survey

Est

imat

ed f

uel

eco

no

my

imp

rove

men

t

(vs

5W-3

0 O

IL B

), %

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0HTHS viscosity, mPa ･s

Formulation AFormulation B

With Mo

Without Mo

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0HTHS viscosity, mPa･s

Formulation A

Formulation B

With Mo

Without Mo

L4, 1.8L, Bucket typeL4, 2.0L, Roller Rocker Arm type

0W200W20 0W/200W/20

0W100W10？？0W100W10？？

5W305W305W305W30

Est

imat

ed f

uel

eco

no

my

imp

rove

men

t

(vs

5W-3

0 O

IL B

), %

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0HTHS viscosity, mPa ･s

Formulation AFormulation B

With Mo

Without Mo

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0HTHS viscosity, mPa･s

Formulation A

Formulation B

With Mo

Without Mo

L4, 1.8L, Bucket typeL4, 2.0L, Roller Rocker Arm type

0W200W20 0W/200W/20

0W100W10？？0W100W10？？

5W305W305W305W30

Source:SAE 2002-01-1636Source:SAE 2002-01-1636

HTHS Viscosity vs. Fuel Economy

Temperature → High

HT

HS

Vis

cosi

ty, m

Pa

・s

150℃

80℃

↓Low

High VI Oil

Current Oil (0W-20)

●2.6

Fuel EconomyFuel Economy●

●

●

Viscosity Reduction of Current Oil (0W-10 ?)

Engine ProtectionEngine Protection

Necessity of High VI Oil for Fuel Economy and Engine Protection

Ultra Low Viscosity Engine Oil(Example: Draft ILSAC GF-5 0W-20)

1. Fresh Oil Viscosity Requirements1.a SAE J300

• KV100 5.6 – 9.3• HTHS150 ≥ 2.6• CCS -35 ≤ 6200• MRV -40 ≤ 60000

1.b Gelation Index

2. Engine Test Requirements2.a Wear and Oil Thickening (Seq IIIG)2.b Wear, Sludge and Varnish (Seq VG)2.c Valvetrain Wear (Seq IVA)2.d Bearing Corrosion (Seq VIII)2.e Fuel Efficiency (Seq VID)

• Fresh Oil Fuel Economy• Aged Oil Fuel Economy

2.f Used Engine Oil Aeration Test

3. Bench Test Requirements

3.a Catalyst Compatibility• P ≤ 0.07 mass%

3.b Wear• P ≥ 0.06 mass%

3.c Volatility

3.d High Temp. Deposit (TEOST MHT)

3.e High Temp. Deposit (TEOST 33C)

3.f Filterability

3.g Fresh Oil Foaming Characteristics

3.h Fresh Oil High Temp. Foaming

3.i Aged Oil Low Temp. Viscosity (ROBO)

3.j Shear Stability (Seq VIII)

3.k Homogeneity and Miscibility

3.l Engine Rusting (Ball Rust Test)

3.m Emulsion Retention

3.n Rust Protection Test

Influences of Engine Oil Compositionon Performances

Component Direct Effects Indirect Effects

Base Oil Kinamatic Viscosity Low Temperature Viscosity Volatility Thermal Stability

Oxidation Stability Fuel Economy Foaming / Aeration

Detergent Engine Cleanliness High Temperature Deposit

Homogeneity and Miscibility Emulsion Retention

Dispersant Engine Cleanliness Low Temperature Viscosity (Negative)

Oxidation Inhibitor

Oxidation Stability Wear Protection

Catalyst Compatibility (Negative)

Influences of Engine Oil Compositionon Performances (continued)

Component Direct Effects Indirect Effects

Friction Modifier Fuel Economy High Temp. Deposit (Negative)

Viscosity Modifier Viscosity Thickening Viscosity Index HTHS Viscosity Low Temperature Viscosity Shear Stability

Volatility Fuel Economy Dispersancy Wear Protection

Corrosion Inhibitor Rust Protection Bearing Corrosion

High Temp. Deposit (Negative)

Wax Modifier Low Temperature Viscosity

Antifoam Agent Foaming / Aeration

Formulation Example (GF-4 0W-20)

Items Unit Test Method Result

Formulation Yubase 4 DI Package Viscoplex 6-850

mass%mass%mass%

85.9310.723.35

Kinematic Viscosity (@40C) mm2/sASTM D 445

43.16

Kinematic Viscosity (@100C) mm2/s 9.178

Viscosity Index ASTM D 2270 202

CCS Viscosity (@-35C) mPa-s ASTM D 5293 5,555

MRV TP-1 Viscosity (@-40C) mPa-sASTM D 4684

18,600

Yield Stress (@-40C) Pa < 35

Pour Point C ASTM D 97 - 42

HTHS Viscosity (@150C) mPa-sASTM D 4683

2.65

HTHS Viscosity (@100C) mPa-s 5.49

Noack Volatility % ASTM D 5800 14.08

Viscosity Modifiers for Ultra Low Viscosity Engine Oil

OCPs• Higher thickening efficiency Lower base oil viscosity

Higher volatility• Limitation in Viscosity Index improvement• Poor low temperature performances

PAMAs• Lower thickening Higher base oil viscosity Lower volatility• Provides higher flexibility in base oil selection• Higher Viscosity Index Better Fuel Economy• Excellent low temperature performance• Flexibility in molecular design

– Dispersancy Reduction of ashless dispersants Better low temperature performance + cost effectiveness

– Additional functions Film thickness / Low friction

Summary

Requirement for vehicle fuel economy is becoming more and

more stringent in next few years to reduce CO2 emission

Low friction engine oil is one of the countermeasures for

improving fuel economy

Ultra low viscosity engine oils such as SAE 0W-20 have been

used in Japan

PAMA provides various advantages and flexibilities for

formulating ultra low viscosity engine oils, thus contributes fuel

saving of automobile