Heavy Duty Engine Oil Technology
Comparison of European and US
Developments
2 Contents
Operating Conditions and drivers for lubricant requirements
Comparison of Heavy Duty Engine Oil make-up in Europe and America today
Approach to low emission engines in Europe
Aftertreatment sensitivity to Heavy Duty Engine Oils
– Some technical proof
3 Operating Conditions
Europe North America
avg. annual mileage, miles 62,500 125,000
Gross Vehicle weight, tonnes 40 36 (80000 lb)
Power output 350 bhp 350 bhp
Avg sump volume, L 35 35 - 40
Avg diesel cost, USD per gal 4.03 1.69
Oil Drain interval, miles 15,000 to 75,000 20,000
In Europe, engine manufacturers recommend highly extended oil drain
– Oil performance level, engine type, operating cycle, load
– Oils must pass specific field test or fired engine test requirement for use in extended drain
In Europe, fuel costs typically equate to 30% total fleet cost
– fuel efficient lubricant can result in high cost savings
drive towards lower viscosity levels, synthetic basestocks
4Can the lubricant protect the engine at extended drains?
Connecting rod bearings
Typical piston
Synthetic, high ash heavy duty engine oil
Inspection at end of trial : 3 x 100,000 km
5 Composition of Heavy Duty Engine Oil
API CG-4soot handling
oxidation stability
API CI-4VTW,
soot/ acid controloxidation stability
High dispersancyLow dispersancy
High ash(up to 2.0%)
Low ash
API CH-4VTW
soot handlingoxidation stability
ACEA E5deposits, VTWsoot handling
oxidation stability
ACEA E4piston
deposits
soot loading, piston temps, peak combustion pressure
piston cleanliness, oil drain interval, fuel savings
EuropeEurope
AmericaAmerica
6Evolution of FormulationsOil Performance in Field
Al Cr Cu Fe Pb Sn
Average Wear Rates
CH-4 CI-4
Evolution of engine oil make-up to meet new emissions
– Is there a benefit to the operator?
Improved wear protection for CI-4 oil versus CH-4 oil
7 The Future : Low Emission Timeline
2000 2005 2007 2008 20092003 200420022001 2006 20112010 2012
Euro 3 Euro 4 Euro 5
Tax IncentivesFor Euro 4/5(Germany)
US 2007Implementation
Euro 6
Low sulphur fuel required
Drive towards low S basestocks
8 European After-treatment choices
For Euro IV
– SCR only will be the preferred choice
– Fuel economy (+), no oil sensitivity (+), infastructure (-), NH3 slip (-)
– EGR + DPF is also a likely option
– Fuel economy (-), TBN maintenance (?), reduced drain (?)
– DPF will be used where necessary ; urban fleets, city buses
For Euro V
– If limits allow, approach will be the same as Euro IV
– If limits change then SCR and DPF will be required
Proposed European HDEO specifications for 2005 :
Proposed Spec ACEA E6 ACEA E7
Sulphated ash <1 %
Phosphorous <0.08%
Sulphur <0.3%
Other ACEA E4 performance ACEA E5 performance
9Effect of low sulphur diesel on lubricant TBN
Less stress on lubricant with low sulphur fuel
0
2
4
6
8
10
12
14
16
0 5000 10000 15000 20000
High Sulphur Fuel TBN
High Sulphur Fuel TAN
Low Sulphur Fuel TBN
Low Sulphur Fuel TAN
Mileage accumulation (miles)
mg
KO
H/g
Oil drain intervals can be maintained
High sulphur = 6000 ppm S Low sulphur = 50 ppm S
10
Can we improve exhaust after treatment compatibility and emissions with the lubricant…………..
11 SCR Particulate Size vs Number
Particulate size vs number
10000
100000
1000000
10000000
1 10 100 1000
Diameter (nm)
dN
/ d
l(D
p)
[/cm
3]
A B C D E F G H I
12 litre bus engine with SCR after-treatment system
– Calibrated to Euro V NOx emissions level (<2 g/ kWh)
No lubricant effect on particulate emissions post SCR
Matrix of oils A to IVarying ash levelVarying baseoil Gp
12 Ash accumulation in DPF
Ash Accum in 200 hours
0
5
10
15
20
25
High Ash 5w30 Low Ash 5W30 Med Ash 15w40
Gram
mes
Oil Consumed in 200 hours
0
1
2
3
4
5
6
High Ash 5w30 Low Ash 5W30 Med Ash 15w40
Kilo
gram
mes
12.7 litre HD engine with CRT200h max power, max speed
Weight of trap deposits corresponds to s-ash of the oil
Trials in progress to evaluate impact on DPF life in field
13 Ash Sensitivity of DPF
Ash speciation
0% 20% 40% 60% 80% 100%
1
2
3
1
phos sulphur zinc calcium magnesium
Fresh Oil Component Ratio's
0% 20% 40% 60% 80% 100%
1
2
3
1
phos sulphur zinc calcium magnesium
Electron Dispersive Spectroscopyanalysis of deposits on trap face
Ratios of ash speciation correlate to fresh oil components
14
Euro IV will require reduction in ash, P, S. May result in
Reduced Drain intervals
Increase in synthetic oils to improve volatility and oxidation stability and reduce sulphur
Challenge to satisfy conflicting requirements of EGR + DPF
Closing Thoughts
Until 2007, engine technology different in each market
Market dedicated HD engine oil development
Post 2007, harmonisation of emission legislation
Market differences reduce
EO development driven by individual OEM strategies
Opportunity for truly global HDEO specification?