3. 1- Why? Reduce friction
A lubricant aims to separate moving parts to reduce the
friction which causes heating & surface wear.
With lubricant !!
Without
lubricant
Friction No Friction
Heat of parts, wear
& higher resistance to
movement.
4. Under a microscope, even a well polished metallic surface
looks like rugged terrain
Using lubricants makes things easier !
Why? Reduce friction
5. Hydrodynamic lubrication
There are 3 states of lubrication determined by the thickness of oil film
There are 3 states of lubrication determined by the thickness of oil film
and the roughness of metal surfaces.
and the roughness of metal surfaces.
Mixed lubrication
Boundary lubrication
Why? Reduce friction
6. • Reduce friction
PLUS
Evacuate heat
Avoid accumulation of deposits (sludge, vanish…)
Protect against rust & corrosion
Disperse foreign material (water, dust …)
Improve seal effectiveness
Reduce friction and …
7. WHAT DO ENGINE LUBRICANTS DO?
2 main roles
Friction reduction
- To resist wear
- To reduce fuel consumption
Engine cleanliness
8. WHAT LUBRICANTS DO
Additional roles
Sealing
- Piston rings
Corrosion resistance
- Action of O2 in air + humidity + heat
- Pollutants: Acid, Sulphur ...
Engine cooling
- To absorb and carry off heat
11. ENGINE CLEANLINESS
NEUTRALIZES AND REMOVES ENGINE CONTAMINANTS
• soot and unburned particles
• wear debris and particles
• lubricant breakdown products (varnish, carbon, sludge…)
• water, coolant…
12. TEMPERATURE REDUCTION
A role in engine cooling
LOWERING OF OPERATING TEMPERATURES
• Friction energy is dissipated entirely as heat (the contact
temperature of surfaces rises proportionally to the friction
coefficient).
Fluid lubricant carries heat away from the hot region of an engine
16. Base Oils Additives
+
Final product
• Mineral oils
• Synthetic oils
(PAO, PAG …)
One or several
packages if
requested
Lubricants - Composition
17. • Why do we need additives ??
– To enhance existing properties already included in base oils :
To enhance existing properties already included in base oils :
– Pour point, viscosity index & anti-oxidant property.
– To add new properties to the final product :
To add new properties to the final product :
– Detergent, dispersants, anti-corrosion & anti-rust properties,
anti-wear & extreme-pressure properties...
Lubricants - Composition
19. Lubricants - Characteristics
•Main physical & chemical
physical & chemical characteristics
Viscosity & Viscosity Index
Pour point
Flash point & Fire point
Resistance to oxidation
Anti-foam & air release properties
Anti-rust & Anti-corrosion properties
Dispersant & Detergent properties
•Main mechanical
mechanical characteristics :
Anti-wear & Extreme-Pressure properties
20. Viscosity
Definition :
Definition :
Resistance of an oil to flow
Resistance of an oil to flow
: Kinematics viscosity
: Kinematics viscosity (mm²/s or Cst)
(-> the most frequently used)
• Viscosity goes down when temperature increases
22. • Viscosity goes down when temperature increases
this variation is determined by the Viscosity Index
Viscosity Index (VI)
(VI)
High variation with temperature : Low VI
Small variation with temperature : High VI
• Mineral base oils : VI 100
• Mineral base oils with a VI improver : VI 150
• Synthetic base oils : VI 150
Viscosity Index : VI
The VI is useful to determine the viscosity
of an oil at low or high temperature
24. Viscosity Modifiers (VM)
• PURPOSE
due to its effectiveness, the lubricant is:
– viscous enough to avoid contact between moving parts at high
temperature
– fluid enough to facilitate starting up at low temperature
• HOW DOES IT WORK?
A02-35.PPT
At high temperature, big volume of molecule:
– resistance to flow
– Thick lubricants
At low temperature small volume of molecule :
– weak resistance to flow
– Thin lubricants
Temperature Additive
molecule
25. Pour point
•Definition :
The lowest temperature at which the lubrication oil can still be poured (it
can reach -50°C).
The pour point is defined by several equivalent standard test methods:
NFT 60105, ASTM D 97, ISO 3016.
26. Flash point & Fire point
•Definition :
The Flash point is the lowest temperature of spontaneous ignition of
the vapours of oil with a flame, while it is heated.
The Fire point is the lowest temperature when the ignition is followed by
the combustion of oil itself.
NB:
These 2 characteristics are key parameters for Heat Transfer Fluids.
The flash point is between 200°C & 250°C.
27. Resistance to oxidation
•Definition of the oxidation :
Oxidation of lubricants is a chemical reaction.
The main consequences are
• increase of the viscosity,
• production of acids (attack surfaces)
• insoluble products (sludge).
Some parameters can act as catalyst in this chemical reaction :
• presence of air,
• high temperature,
• presence of some special metals.
28. Behaviour in presence of air
•Definition :
The presence of air in a lubrication circuit can
cause serious damage
decrease performance levels and
produce surface foaming
Lubricants must have anti-foam & air release properties particularly,
when the possibility of the introduction of air bubbles is high, e.g. splash
lubrication.
29. Anti-rust & anti-corrosion properties
•Definition :
Lubricants
protect metal parts against
• acids
• O2 and H2O
prevent
• corrosion
• rust.
30. Dispersant & Detergent properties
•Definition :
Detergency:
Lubricants keep metal surfaces clean, without any deposits produced by
chemical reaction, e.g. sludge and varnish.
Dispersion:
Lubricants keep in suspension, insoluble contaminants & prevent
them from clogging lubrication circuit
31. Anti-Wear & Extreme-Pressure (EP)
properties
•Definition :
Lubricants reduce friction.
When the lubricated part is heavy loaded, the oil film between the moving
parts becomes under high pressure, a direct metal surface contact can
occur, if the oil film is disrupted.
Consequence:
Lubricants must have anti-wear & extreme-pressure properties in order to
prevent direct metal surface contact.
32. Anti-wear : 4-ball test
Moving ball
Fixed balls
Load
40 Kg
Oil sample
RPM : 1 200
( ASTM D 4172 )
3 balls are kept stationary ; a
fourth ball attached to the chuck
rotates at 1200 RPM for 1 hour.
Measurement of wear
33. Base Oils
Mineral Base Oils
– classical mineral oils
– Hydro treated
Synthetic Base Oils
– PAO : Poly Alpha Olefins
– PAG : Poly Alkylen
Glycols
– Alkyl benzenes
– Esters
– Polyisobutenes
Base Oils
From crude oils
Petroleum Refinery
From petrochemical
& chemical industries
39. Properties Of Mineral Base Oils
Hydrorefining Hydrocracked Hydroisomerised
(HVI) (HC) (XHVI)
90- 95 95-105 130 140
+ ++ ++ +++
- 10°C / -15°C - 10°C / -18°C -15°C - 15°C / -18°C
+ ++ +++ ++++
1 1 3 4.5
Pour Point
Cost
Low Aromatics
ratio
Hydrotreated
Mineral
Solvent
(NS / BSS)
Viscosity Index (VI)
Resistance to oxidation
+++ Very good
++ Good
+ Normal
40. Synthetic Base Oils / Comparison Chart
PAO PAG Esters Alkylbenzene PIB
0.9 0.85 0.9 - 1.1 0.9 0.85 < 0.95
80 - 100 135 150 - 200 100 - 250 20 < 100
+ ++ - +++ +++ -
+ +++ ++ +++ ++ ++
+ +++ ++ ++ - -
1 4 - 6 4 - 5 4 - 10 3 - 4 3
Cost
Mineral oils
(NS / BSS)
Synthetic Base Oils
VI
Thermal
Stability
Low pour point
Low volatility
Specific
Gravity
+++ Very good
++ Good
+ Normal
- Bad
41. Notes : - (1) (2) 1 mPa.s = 1 cP; 1 mm²/s = 1cSt; All values are critical specifications as defined by ASTM D 3244
- (3) : 0W-40, 5W-40 and 10W-40 Grades
- (4) : 15W-40, 20W-40, 25W-40 and 40 Grades
SAE Low temperature (°C) Pumping viscosity (mPa.s) Kinematic viscosity High temperature (150°C)
viscosity Cranking viscosity at low temperature (°C) (mm2/s) at 100°C high shear (10
6
s
-1
)
grades (mPa.s) ASTM D 4684 ASTM D 445 HTHS Viscosity (mPa.s)
ASTM D 5293 MRV ASTM D 4683
CCS No yield stress Min Max CEC L-36-A-90
(ASTM D 4741 or D 5481)
0W < 6200 at - 35 < 60 000 at - 40 > 3.8 -
5W < 6600 at - 30 < 60 000 at - 35 > 3.8 -
10W < 7000 at - 25 < 60 000 at - 30 > 4.1 -
15W < 7000 at - 20 < 60 000 at - 25 > 5.6 -
20W < 9500 at - 15 < 60 000 at - 20 > 5.6 -
25W < 13000 at - 10 < 60 000 at - 15 > 9.3 -
20 - - > 5.6 < 9.3 > 2.6
30 - - > 9.3 < 12.5 > 2.9
40 - - > 12.5 < 16.3 > 2.9 (3)
40 - - > 12.5 < 16.3 > 3.7 (4)
50 - - > 16.3 < 21.9 > 3.7
60 - - > 21.9 < 26.1 > 3.7
SAE Viscosity Grades for Engine Oils (1)(2)
42. SAE (J 306C) GEAR OIL CLASSIFICATION
SAE
Viscosity
Grades
Maximum temperature
(°C) for a BROOKFIELD
viscosity of 150 000 cP
(ASTM D 2983)
K.V. at 100
Dc, cSt
(ASTM D 445)
Min. Max.
70W -55 4.1 N.R
75W -40 4.1 N.R
80W -26 7.0 N.R
85W -12 11.0 N.R
80 N.R 7.0 11.0
90 N.R 13.5 24.0
140 N.R 24.0 41.0
250 N.R 41.0 -
43. GREASES NLGI Classification
NLGI No. Worked Penetration, 25 C
(60 strokes)
Description
000 445 - 475 Very fluid
00 400 - 430 Fluid
0 355 - 385 Semi fluid
1 310 - 340 Soft
2 265 - 295 Medium
3 220 – 250 Medium firm
4 175 - 205 Firm
5 130 - 160 Very firm
6 85 - 115 hard
44. Industrial Oils ISO VG Classification
Viscosity Grade (VG)
2
3
5
7
10
15
22
32
46
68
100
150
220
320
460
680
1000
1500
Indicates
viscosity of oil
within 90-110
cSt at 40 C
This classification
indicates lubricant
viscosity at 40 C
within 10% range
45. Lubricant specifications and categories
General
Viscosity category: SAE J300
lubricant viscosity grade
International and automaker specifications
lubricant performance
- laboratory tests
- mechanical tests
- engine tests
46. Specifications for passenger car engine oils - General
International specifications
Automaker specifications: PSA, RENAULT, VW, MB, BMW…
Certification systems
API / ILSAC ACEA (CCMC pre-1996)
Licensing system
“Donut” on packaging
Audit of marketed products
Self-certification
Packaging labels
47. API / ILSAC specifications
C A
.
.
.
.
.
C D
C F
diesel severity
1945
1965
1995
S A
.
.
.
S G
S H
S J
S L
gasoline
severity
1945
1988
1993
1996
1st
letter indicates the type of service
2nd
letter indicates the performance level
DONUT
US
2001
48. API CLASSIFICATIONS – ENGINE OILS
Designation “S” represents Service (Petrol engines)
Designation “C” represents Commercial (Diesel engines)
API CA, CB / SA to SE Inactive
API CC, CD, CD-II, CE,
CF, CF-II, CF-4, CG-4, CH-4 Active
SF, SG, SH, SJ and SL
Higher the designations, superior the oil quality
In India, prevalent diesel oils meet specification of API CC, CD
and CE. OEM’s like TELCO, Ashok Leyland, CUMMINS,
Caterpillar have started shifting to API CF-4 levels.
For petrol engines, prevalent specifications are of API SF &
SG
50. US MILITARY & BIS ENGINE OIL CLASSIFICATIONS
US Military Classification
* US MIL-L-2104 A till US MIL-L-2104 F
* In the Indian context, MIL-L-2104 B and MIL-L-2104 C use
still pre-dominant.
BIS CLASSIFICATION (IS 13656 : 1993)
* E-DL 1(API CC) * E-PL 2 (API SF)
* E-DL 2(API CD/CF) * E-PL 3 (API SG)
* E-DL 3(E-DL 2 + Mack T-7/T-8A) * E-PL 4 (API SJ)
* E-DL 4 (API CF-4)
* E-DL 5 (API CF-4 + ACEA E2)
* E-DL 6 (ACEA E3)
52. Multi-grade Vs Mono-grade Oils
1. SAE Classification classifies Engine & Gear oils as per
their viscosity only.
2. 11 grades for Engine Oils & 8 grades of Gear Oils
identified,
SAE 0W SAE 70W
5W 75W
10W 80W
15W 85W
20W 80
25W 90
20 140
30 250
40
50
60.
Higher
the
grade,
more is
the
viscosity
.
Oil meeting
requirement of
one SAE
classification is
called
monograde oil.
All these grades
independently
are monogrades
53. I
n
c
r
e
a
s
i
n
g
v
i
s
c
o
s
i
t
y
25 W
20 W
15 W
5 W
50
30
20
A03-16.PPT
10 W
0 W
40
60
Monograde lubricants : one SAE number (SAE 10W, SAE 30...)
Multigrade lubricants : two SAE numbers xxW-yy ( SAE 5W-40, SAE 10W-30, SAE 20W-50...)
VISCOSITY CLASSIFICATION
SAE J300
54. Viscosity - Temperature Relationship
Too thick when cold
Too thin
when hot
(SAE 40)
(SAE 15W)
(SAE 15W 40)
THICK
THIN
0 C
(Winter start
temperature)
150 C
(Engine opera-
ting temp.)
40 C 100 C
55. MULTIGRADE OILS
1. Oils meeting the requirements of more than one
SAE classification.
Examples of multigrades:
5W 50, 15W 40, 20W 40, 20W 50 etc..
2. ‘W’ stands for Winter.
3. Are oils for round the year use, exhibiting constant
viscosity over a wide temperature range.
Monogrades exhibit viscosity increase with
decreasing temperatures, and vice versa.
4. Provide less wear and tear due to easy cold
cranking. IMPROVES ENGINE LIFE.
56. MULTIGRADE OILS
5. Their usage prolongs the life of the starting system.
6. Give Improved fuel efficiency
7. Less oil consumption between changes due to
better viscosity retention at higher temperatures.
FEWER TOP-UPS
Editor's Notes
#1:This stylesheet is to be used for internal mettings. The following layout principles must be respected.
Welcome screen:
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The other elements of this screen are locked and should not be changed in any way.
#33:The amount of wear is calculated by measuring the diameter of the indentations in three balls, caused by the rotation of the 4th ball.
If the EP property is not high enough, the surfaces fuse together.
