Transcript Engine Lubricants and Lubricating Systems

Engine Lubricants
and
Lubricating Systems
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AGSM 201 Slides Page:
<http://baen.tamu.edu/users/lepori/agsm_power_point_slides.htm>
Functions of Engine Oils
1.
2.
3.
4.
5.
6.
7.
Reduce wear
Reduce friction
Seal Compression
Reduce noise
Cool engine parts
Reduce rust
Keep parts clean
Organizations Providing
Uniform Standards for Oil
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S.A.E.
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A.P.I.
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Society of Automotive Engineers
American Petroleum Institute
A.S.T.M.

American Society of Testing & Materials

American Automobile Manufacturers
Association
 Engine Manufacturers Association
 I.S.O.

International Standards Organizations
Properties of Motor Oils
 Viscosity
 Viscosity
Index (VI)
 Flash Point
 Pour Point
 Per cent sulfated ash
 Per cent zinc.
Properties of Motor Oils
 Viscosity
 Viscosity
Index (VI)
 Flash Point
 Pour Point
 Per cent sulfated ash
 Per cent zinc.
Viscosity
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Measure of the "flowability“
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Property –
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Resistance to flow
Shearing stress
High viscosity - thick oils
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Kinematic
Dynamic
Too high viscosity may not reach all parts
Low viscosity – thin oil
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Too low viscosity may not provide enough strength
to keep parts from wearing
Dynamic & Kinematic
Viscosity
Kinematic Viscosity Measurement
Saybolt Viscometer
Glass capillary viscometers
Dynamic Viscosity Measurement
Typical Brookfield Viscometer
Weight of oils

Common term identifying viscosity for oils
 Numbers assigned by the S.A.E.
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correspond to "real" viscosity, as measured by
accepted techniques.
These measurements are taken at specific
temperatures.
Oils that fall into a certain range are designated 5,
10, 20, 30, 40, 50 by the S.A.E.
The W means the oil meets specifications for
viscosity at 0 F and is therefore suitable for Winter
use.
_______________________________________________________________
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SAE Gear Viscosity Number
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|75W |80W
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|____|_____|___|______________|________________________|
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|85W|
90
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140
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SAE Crank Case Viscosity Number
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____________________________
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|10| 20
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|__|_____|____|_____|______|
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| 30 | 40
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50
______________________________________________________________
2
4
6
8
10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
viscosity cSt @ 100 degrees C
Properties of Motor Oils
 Viscosity
 Viscosity
Index (VI)
 Flash Point
 Pour Point
 Per cent sulfated ash
 Per cent zinc.
Viscosity index

The measure of an oil's ability to resist
changes in viscosity when subjected to
changes in temperature.
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As temperature increases
viscosity decreases.
Low temperatures –
High viscosity
High temperature –
Low viscosity
Multi-viscosity/Multi-grade Oil

Oil meeting SAE requirements for
both low-temperature
requirements of light oil and hightemperature requirements. Also
know as multiweight oil.
 Oil that meets certain lowtemperature and hightemperature requirements
simultaneously
 (e.g., SAE l0W-40).
Properties of Motor Oils
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Viscosity
Viscosity Index (VI)

Flash Point
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Pour Point
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Minimum sample temperature at which vapor is
produced at a sufficient rate to yield a combustible
mixture.
The lowest temperature at which oil will pour.
Per cent sulfated ash
Per cent zinc.
Properties of Motor Oils
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Viscosity
Viscosity Index (VI)
 Flash Point
 Pour Point
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Percent sulfated ash
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how much solid material is left when the oil burns.
A high ash content will tend to form more sludge
and deposits in the engine.
Low ash content also seems to promote long
valve life. Look for oils with a low ash content.
Per cent zinc.
Properties of Motor Oils
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Viscosity
Viscosity Index (VI)
Flash Point
Pour Point
Per cent sulfated ash
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Percent zinc
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the amount of zinc used as an extreme pressure,
anti-wear additive.
The zinc is only used when there is actual metal to
metal contact in the engine. Hopefully the oil will
do its job and this will rarely occur, but if it does,
the zinc compounds react with the metal to
prevent scuffing and wear.
A level of 0.11% is enough to protect an
automobile engine for the extended oil drain
interval, under normal use.
Common motor oil additives
 Viscosity
index improvers
 used
to enhance the base qualities of the
oil, and to keep the oil from thinning too
much as heat increases.
 Pour-point
 prevent
depressants
crystals from forming in extreme
cold conditions, and consequently lower
the oil's pour point (temperature at which it
pours).
Common motor oil additives
 Oxidation
inhibitors
 help
prevent the oil from oxidizing (in other
words, burning). When oil oxidizes, it loses
its ability to protect the engine. It also
produces sludge deposits and traps
corrosive acids.
 Rust-corrosion
 help
inhibitors
prevent and neutralize water and
oxygen from acid-etching the metals in the
engine and forming rust particles. If this
corrosion were to happen, some complex
acids would form and other sludge
problems would occur.
Common motor oil additives
 Dispersants

help the oil to absorb and retain contaminants
such as dirt or tiny metal particles (from
engine wear) until the oil passes through the
oil filter, where the contaminants are trapped.
 Detergents
 help
to remove contaminants from the engine
components and hold them in the oil until it
reaches a filter, or until it is changed the next
time. They don't only clean up a dirty engine.
Common motor oil additives
 Friction

modifiers/wear inhibitors
"stick" to engine surfaces better, reducing
friction and improving fuel economy. Oils with
the "energy conserving" labels contain friction
modifiers.
 Foam
inhibitors (Antifoamants)
 prevent
the oil from being whipped into many
tiny air bubbles. Air bubbles don't lubricate.
This also helps prevent sludge formation when
the emulsion process is a possible threat in an
engine.
Types of Motor Oils
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Petroleum Based
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Refined from crude oil
Supplemented with additives
Synthetic
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Lubricants chemically engineered from pure chemicals
rather than refined from crude oil.
Can provide significant advantages over refined oils.
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Longer oil change intervals
Longer engine life
Increase gas mileage
More expensive
What the h___ is he talking about?
Items that tell us about selecting an oil!
What the h___ is he talking about?
 How
to select an oil for different
purposes.
 What
to look for on an oil container.
What Oil
Should
You Use
API “Donut”
Gasoline
Service
Classification
Diesel
Engine
Classification
Lubrication Systems
 Splash
 Dipper
 Slinger
 Force
Feed & Splash
 Full Force Feed
Splash Lubrication
Force Feed and Splash
Full Force Feed
Oil Pump
Oil pump intake screen
Engine Oil Degradation and
Contamination
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Oil thickening
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Fuel
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Hydrocarbon compounds
Combustion Products
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Oxidation
Vaporization of lighter
components
Carbon
Water
Sulphur Oxides
Fuel chemical additives
Dust and Dirt
Metal – from wear of
components
Oil Filtration Systems
 By-Pass
–Flow
 Shunt
 Full
Engine
Lubrication
System with
both by-pass
and full-flow
filtration
Two filters provide ability to filter
smaller particles
Filter elements
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Surface
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Pleated paper
Metal screen
Depth
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Cotton waste
Changing oil and filters renews
engine protection

Dirty oil reduces life of an engine.
 Reduce maintenance and increase engine life
by changing engine oil and filters on a
regularly scheduled basis.
 Interval between changes depends on
operating conditions.
 Oil analysis provides management of oil
change intervals

Recommend for fleet operations.
Oil Pressure – Important Sensor
Low pressure light indicator
Lubrication Links on the Web
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Motor oils and more
Motor Oil Functions & Properties
Selecting motor oils
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Motor Oil Additives
Lubrication Systems
Filtration Systems
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API Starburst and Donut
Sources of oil contaminants
Filters & filter media
Synthetic oil base stocks
Synthetic oil history
Oil Analysis –
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Example 1
Example 2