Lubrication/Bearings/Gears

Field Operator Certification

Lubrication/Bearings/Gears
 Lubrication/Bearings/Gears

Lesson Objectives
1. Describe the purpose of lubrication.
2. Describe the principles of Lubrication.
3. Describe the different types of lubricants.
4. Describe the different types of lubrication systems.
5. Describe the types of equipment that require lubrication.
6. Describe the filtration process and methods.
7. Describe the best practices and inspections for Lubrication
systems.
8. Describe the troubleshooting for common Lubrication
problems.
9. Identify safety hazards associated with Lubrication.
10. Perform inspections on the Lubrication systems.
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Objective 1 - Purpose

 The purpose of lubrication is to reduce friction,

prevent wear, remove heat and prevent rust
and corrosion.

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Objective 2 - Principles of Lubrication

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Principles of Lubrication (cont’d)

 Lubrication Terms and Principles
 Friction
 A force that a body must overcome when it slides across
another.
 Solid or sliding friction occurs mainly due to “asperities”
(roughness) present in the two surfaces that rub together.
 Whenever friction is overcome, dislocation of the surface
particles generates heat that could become destructive.
 Lubrication
 The principle of supporting a sliding load on a friction-
reduction film is known as lubrication.
 The substance of which the film is composed is a lubricant,
and to apply it is to lubricate.
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Principles of Lubrication (cont’d)

 Lubrication categories

 Hydrodynamic lubrication
 Oil Wedge is Formed
 Surface Contact Area is
Flooded

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Principles of Lubrication (cont’d)

 Lubrication categories (cont‟d)

 Elastohydrodynamic
lubrication (EHL)
 Film Developed
Between Two Heavily
Loaded Surfaces in
motion
 Oil Viscosity Increases
as it is Forced into Load
Zone

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Principles of Lubrication (cont’d)

 Lubrication categories (cont‟d)

 Boundary lubrication
 Very Thin Film of
Lubrication
 Film Strength Additives
Must be Used

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Principles of Lubrication (cont’d)

 Lubricants
 All liquids will provide lubrication to a degree, but
some do it a better than others. There are two main
groups of lubricants, oil (petroleum) lubricants and
grease lubricants.
 For almost every situation, petroleum products have
been found to excel as lubricants.

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Principles of Lubrication (cont’d)

 Lubricant Properties
 Viscosity is one of the main properties of any oil
lubricant. It is the measure of a lubricant‟s resistant to
flow
 Viscosity is commonly measured by petroleum
industry in centistokes, which numerically equal to
mm2 (square)/s
 Viscosity is often the first consideration in selecting
lubricant oil for specific applications

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Principles of Lubrication (cont’d)

 Lubricant Properties - Viscosity (cont’d)
 Operational condition VS viscosity needed
 Higher load requires high viscosity
 Higher temperature requires higher viscosity
 Increased speed requires lower viscosity

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Principles of Lubrication (cont’d)

 Lubricant Properties - Viscosity (cont’d)

VISCOSITY CLASSIFICATIONS
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Principles of Lubrication (cont’d)

 Lubricant Properties (cont’d)
 Viscosity index. Lubricants tend to thin out when
heated and to thicken when cooled.
 The property of resisting changes in viscosity due to
changes in temperature can be expressed as the
Viscosity Index (VI).
 The higher the VI number of an oil, the less the
tendency for its viscosity to change with changes in
temperature.

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Principles of Lubrication (cont’d)

 Lubricant Properties – Viscosity index (cont’d)

Viscosity Index Graphic For Two Lubricants

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Principles of Lubrication (cont’d)

 Lubricant Properties (cont’d)
 Pour point. The lowest temperature to which oil can be
chilled and still poured from a container is approximated
by its pour point.

Lubricants With Different Pour Point

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Principles of Lubrication (cont’d)

 Lubricant Properties (cont’d)
 Flash point. Minimum temperature at which sufficient
liquid is vaporized to create a mixture of fuel and air that
will burn if exposed to a source of spark.
 Consistency or penetration number (greases). The
consistency of lubricating grease is defined as its
resistibility to deformation under an applied force, in
other words its relative stiffness or hardness.
 Dropping point. The temperature at which the oil
separates from the thickener.
 Structural stability. The ability of the grease to resist
changes in consistency during mechanical working.
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Objective 3 – Types of Lubricants

 Mineral Oils
 Consist of base oil and additives which determine their
performance characteristics.
 The base oil is responsible for the typical properties of
oil. The additives, however, determine its actual
performance by influencing the base oil‟s.
 Oxidation stability
 Anticorrosion properties
 Wear protection
 Wetting behaviour
 Viscosity-temperature behaviour
95% of lubricants are derived from petroleum crude oil.
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Types of Lubricants (cont’d)

 Mineral Oils (cont’d)

Oil lubricant Manufacturing Process

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Types of Lubricants (cont’d)

 Synthetic Oils
 Chemically synthesized (polymerization) and designed to
have specific properties.
 Low pour point and /or
 High flash / fire point and/or
 High viscosity index and /or
 Oxidative and thermal stability and /or
 High shear strength

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Types of Lubricants (cont’d)

 Industrial grease
 Is a fine dispersion of an oil-insoluble thickening agent,
usually soap, in a fluid lubricant which is generally
mineral oil.
 Adequate Lubrication
 Prevent Corrosion
 Seal Out Contamination
 Resist Leakage
 Resist Change in Consistency
 Tolerate Some Contamination
 Seal Compatibility
 Suitable for Method of Application
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Types of Lubricants (cont’d)

 Industrial grease (cont’d)

Farval System For Kiln Fed End Seal

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Types of Lubricants (cont’d)

 Grease vs. oil

 Oil  Grease

 Better Lubrication  Leakage Control

 Easier to Fill / Drain  Reduced Maintenance
 Correct Amount More  Acts as a Seal from
Easily Controlled Contamination
 Heat / Cleaning

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Types of Lubricants (cont’d)

 Solid Lubricants
 There are may type of solid lubricant used for different
applications, like synthetic, metallic or mineral powders
such as PTFE (Teflon), copper, graphite, etc.

Kiln Roller Graphite Lubricated

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Types of Lubricants (cont’d)

 Synthetic lubricants
Pure hydrocarbon, manufactured from raw materials
derived from crude oil with a controlled molecular structure
with predictable properties.
 Polyglycols
 Advantages
– Largest Single Class
– High VI (150)
– Good Low Temp Flow
– Good Thermal/ Oxidation Stability
– Low Volatility
 Disadvantages
– Not Compatible w/ Mineral Oils
– Not Miscible w/ Additives Common to Lubricants
– Surface Paint and Finish Effects
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Types of Lubricants (cont’d)

 Synthetic lubricants (cont’d)
Organic esters
 Advantages
– Oldest Type
– Diesters
– Excellent Low Temp
– High VI (140)
– Good Thermal/ Oxidation Stability
 Disadvantages
– Seal Compatibility Concerns
– Additives Not Soluble
– Surface Paint / Finish Effects
– Not Compatible w/ Mineral Oils
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Types of Lubricants (cont’d)

 Synthetic lubricants (cont’d)
Phosphate esters
 Advantages
– Excellent Fire-Resistant Properties
– Fair High Temp Stable
– Low Pour Point
 Disadvantages
– Poor VI Characteristics
– Considerable Effect on Paints and Finishes
– Excessive Seal Swell
– Extremely High Cost
– Not Compatible w/ Mineral Oils

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Types of Lubricants (cont’d)

 Advantages of synthetics vs. conventional
mineral oils
 Longer Life
 Fuel Savings
 Better Cold Weather Start Up
 Better Protection At High Temperatures
 Longer Equipment Life
 Disadvantages of synthetics vs. conventional
mineral oil
 Cost
 Leakage
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Types of Lubricants (cont’d)

 Synthetics vs. conventional mineral oils

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Types of Lubricants (cont’d)

 Additives
 Purpose:
 To improve the performance of the base oil
 Impart entirely new performance characteristics to a
lubricant
 Reduce the rate at which undesirable changes take place

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Types of Lubricants (cont’d)

 Additives (cont’d)
 Antiwear agent (aw)
 Provides chemical film to reduce metal-to-metal contact
when thin films of oil are created.
 Enhances the antiwear characteristics of oil to permit
loadings of double or triple that of non-additized oil.
 ZDP- most popular antiwear agent.
 Can be found in hydraulic oils
 Extreme pressure (ep)
 Reacts with metal surface to provide sufficient antiwear
material to carry even heavier loads than film strength
additives allow
 Can be found in gear oils, greases
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Types of Lubricants (cont’d)

 Additives (cont’d)
 Oxidation inhibitors
 Peroxide decomposers: convert peroxides into harmless
compounds.
 Chain stoppers: interrupt the chain reaction between
oxygen and hydrocarbon radicals to prevent or slow the
formation of acidic material and sludges.
 Metal deactivators: metals that may have catalytic effect on
oxidation are covered by agent. (copper, lead, iron)
 Can be found in engine oil

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Types of Lubricants (cont’d)

 Additives (cont’d)
 Detergent
 Metallic soaps with neutralization and cleanliness power.
 Because of metallic nature it leaves a slight ash when oil is
burned.
 Metals are usually calcium, magnesium, or sodium.
 Can be found in engine oil

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Types of Lubricants (cont’d)

 Additives (cont’d)
 Dispersant
 Helps prevent sludge, varnish and other engine deposits by
keeping particles suspended in a colloidal state.
 usually non-metallic - ash less dispersant
 Can be found in engine oil
 Rust inhibitor
 Plates out on metal surfaces.
 Protective film is formed that protects the surfaces from
contact with water.
 Can be found in gear oils
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Types of Lubricants (cont’d)

 Additives (cont’d)
 Viscosity (VI) improver
 Synthetic, high-molecular-weight polymers which improve
the viscosity index by coiling and uncoiling in response to
temperature.
 Increase the viscosity proportionally, more at higher
temperatures than low.
 Can be found in engine oil
 Pour point depressant
 Improves the low-temperature fluidity of mineral oils and
reduces wax formation at low temperature.
 Can be found in low pour hydraulic oil
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Types of Lubricants (cont’d)

 Additives (cont’d)
 Molybdenum disulfide
 moly: a black, lustrous powder that serves as a dry-film
lubricant
 Can be found in grease
 Defoamant
 Silicone Polymer molecules which attach themselves to air
bubbles in the foam, producing points of weakness.
 Can be found in gear oil

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Types of Lubricants (cont’d)

 Additives (cont’d)

Additive by lubricant type

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Objective 4 – Lubrication systems

 Oil bath
 Mainly used to
lubricate bearings or
low speed gears. The
oil is poured in a
reservoir and as the
part rotates they get
wet by the lubricant.

Oil Bath System Used on Kiln Bearings. Te

bearing is submerged into the oil and a
scoop pick ups the oil to lube the roller
trunion
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Lubrication systems (cont’d)

 Splash
 Very common
lubrication method
used in gearboxes.
As the gear turns, it
picks up oil and
splashes it to the
matching gear tooth
and bearings.
In this reducer the gears pick up the oil from
the bottom of the reservoir and splash it to
bearings and higher gears

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Lubrication systems (cont’d)

 Circulating
system
 Specially used to
control lubricant
temperature or
pump oil to areas
where
conventional
methods would
not work.

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Lubrication systems (cont’d)

 Circulating system (cont’d)

Reducer with circulating system. Oil pump located underneath of the reducer.
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Lubrication systems (cont’d)

 Spray System
 The lubricant is
pumped from a
drum to a set of
nozzles by applying
compressed air.
The lubricant is
sprayed to the gear
periodically for a
pre-determined
period of time
Spray System for Coal mill Gear
depending of gear
size and speed.
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Lubrication systems (cont’d)

 Manually
 Apply grease to bearings. Based on equipment speed and
bearing size, the lubrication frequency and amount is
previously determined.

Grease guns Ultra Sound Tool for bearings Lubrication

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Lubrication systems (cont’d)

 Central System
(Farval)
 A complete
system consists
of the central
station with its
pump, reservoir,
reversing valve,
and timer;
distribution lines
and measuring
valves

Grease Central (Farval) System used in Material

stackers and reclaimers
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Objective 5 - Lubricated equipment

 Three main types of equipment need lubrication:

 BEARINGS - two types, plain and roller element or
antifriction
 GEARS – spur, helical, herringbone, spiral bevel,
tapered roller, worm, plain journal, ball and hypoid
 CYLINDERS - hydraulic pumps
Note: This equipment will be covered in another module.

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Lubricated equipment (cont’d)

 BEARINGS

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Lubricated equipment (cont’d)

 BEARINGS (cont’d)
 Bearings main functions
 Support the Load
 Prevent/Minimize Movement
 Minimize Friction

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Lubricated equipment (cont’d)

 BEARINGS (cont’d)
 Bearing types
 Plain – Friction Bearings
– Advantages: Simple in Design
– Disadvantages: Higher Starting Torque Required
– Type of plain bearing: Journal bearings

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Lubricated equipment (cont’d)

 BEARINGS - Bearing types (cont’d)
 Rolling Element or Anti-friction
– Advantages: Minimal Friction
– Disadvantages: Complex in Design
and Maintenance
– Types of rolling element bearings:
» Roller Bearings: cylindrical,
spherical, tapered, needle
» Ball Bearings: single row, double
row, angular contact

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Lubricated equipment (cont’d)

 BEARINGS (cont’d)
 Types of Bearings and their application
 Needle Bearing – Compact design with space
limitations

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Lubricated equipment (cont’d)

 BEARINGS - Types of Bearings and their
application (cont’d)
 Spherical Roller Thrust Bearings – heavy thrust
loads or combined loads that are predominantly thrust

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Lubricated equipment (cont’d)

 BEARINGS - Types of Bearings and their
application (cont’d)
 Taper Bearing – Radial and axial loads acting
simultaneously; carries thrust in one direction

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Lubricated equipment (cont’d)

 BEARINGS - Types of Bearings and their
application (cont’d)
 Cylindrical Bearings – high radial load capability
and high speed applications with minimal thrust loads

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Lubricated equipment (cont’d)

 BEARINGS - Types of Bearings and their
application (cont’d)
 Spherical Bearings – inherently self-aligning. Can
withstand radial loads and heavy thrust loads carried in
either direction

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Lubricated equipment (cont’d)

 BEARINGS - Types of Bearings and their
application (cont’d)
 Single or Double Row Spherical Bearing – high
speed radial load with moderate thrust.
 Plain Bearing – Automotive rod and main bearings.

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Lubricated equipment (cont’d)

 BEARINGS - Types of Bearings and their
application (cont’d)
 Angular Contact Bearings – heavy thrust load;
minimal radial load

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Lubricated equipment (cont’d)

 Lubricants used for bearings
 Oil
 Grease

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Lubricated equipment (cont’d)

 Methods for lubricating Bearings with oil
 Circulation System: oil is pumped from the reservoir,
through a cooler, to the bearings and drains back to the
reservoir.
 Oil Bath System: Oil Bath System - bearings are
partially submerged in a static oil system (pool of oil).
 Oil Splash System: has a static oil reservoir. Gears
rotating in the oil reservoir splash oil into adjacent
bearings or catch troughs which distribute the oil through
channels to outlying bearings by gravity flow.
 Oil Mist System: delivers very fine particles of oil in a
low velocity, low pressure air stream
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Lubricated equipment (cont’d)

 Methods for lubricating Bearings with grease
 Hand Packing: bearing usually packed by hand.
Bearings should only be 1/3 filled.
 Gun Packing: housing is designed such that re-
lubrication can be performed via grease fitting using a
pressure grease gun.
 Centralized System: Centralized System - supplies
grease with a hand or power operated pump which takes
grease from a reservoir and forces it through supply lines
to bearings.
 Automatic Lubricator ???? Gas activated

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Lubricated equipment (cont’d)

 Advantages to using grease in a bearing
 Better staying capability than oil;good where frequent oiling
intervals are not possible (poorly accessible locations)
 Provides metal separation at low speeds and high loads where
the oil wedge will not form.
 Good sealant for keeping out contaminants (dirt and water)
 Grease – rule of thumb
 The smaller and faster the bearing the more frequent the
interval
 For Every 27 °F increase above 158 °F the interval should be
halved
 Contamination requires more frequent lubrication to purge
system
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Lubricated equipment (cont’d)

 Disadvantages to using grease in a bearing
 Poor cooling ability due to the absence of flow
 Retains contaminants due to the absence of flow
 Grease can separate/harden over time
 Since bearing is used in an oil lubricated gear box; the
grease can contaminate the oil.

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Lubricated equipment (cont’d)

 Causes of Bearing Failures
 Misalignment
 Vibration
 Faulty mounting/installation
 Passage of electric current through the bearing
 Inadequate lubrication
 Improper fits

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Lubricated equipment (cont’d)

 Failure Conditions Present in Bearings
 Smearing: the repositioning of metal from one point to
another on a single surface or the transfer of metal from
one metal surface to its mating surface.
Causes - improper assembly, faulty parts, inadequate
lubrication, excessive speed and shaft misalignment.

 Flaking - surface metal loss in the form of flakes or

scale-like particles. Form of pitting that results from
fatigue.
Causes - attributable to assembly misalignment

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Lubricated equipment (cont’d)

 Failure Conditions Present in Bearings (cont’d)
 Fluting - metal removal, a type of pitting in the form of
ribs, or flutes, in a regular pattern.
Causes - combination of vibration with either passage of
electric current or excessive load.
 Electrical Pitting - metal removal in the form of tiny
pinpoint craters.
Causes - caused by current across gap between
surfaces; proper grounding will correct problem.
 Corrosion - metal loss from chemical attack due to one
or more of the following; presence of water, corrosive
atmosphere, corrosive (oxidized) lubricant and fretting.
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Lubricated equipment (cont’d)

 Failure Conditions Present in Bearings (cont’d)
 Cracks - narrow openings or breaks usually without metal
loss.
Causes - caused by improper fits, housing deformation, etc.,
that over-stress the races.
 Brinnelling - (indentation) surface depressions w/o material
loss.
Causes - impact loading beyond static load capacity on a
stationary bearing; improper mounting and the presence of
abrasive particles.
 Broken or Damaged Races and Cages
Causes - improper mounting, lube starvation and excessive
speed.
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Lubricated equipment (cont’d)

 Failure Conditions Present in Bearings (cont’d)
 Grooves - develop when a hard, abrasive metallic particle
enters a bearing and gets caught in the softer cage pocket,
creating grooves as it rubs against the roller.
 Heat Checks or Thermal Cracking - minute radial cracks
resulting from frictional heat that causes sliding contact within
bearing.
Causes - inadequate lubrication or improper fitting practices
 Handling Damage - during installation and at any time
thereafter, any and all of these can happen: broken flanges,
nicks and burrs, misalignment, machining errors, excessive
preload, and cage damage; great care should be exercised to
prevent such things; otherwise failure is sure to follow.
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Lubricated equipment (cont’d)

 Troubleshooting Potential Bearing Problems
 Excessive heat
 Excessive noise
 Damaged seals
 Excessive leakage
 Oil analysis results showing high metals or contamination

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Lubricated equipment (cont’d)

 Reasons for Grooving/Chamfering Plain
Bearings
 Allow a mechanism for sufficient oil distribution to the
proper areas.
 Oil viscosity in bearings:
 Too High an oil viscosity in a bearing causes:
Overheating
 Too Low an oil Viscosity in a bearing causes: Too much
metal-to-metal contact resulting in excessive wear and
eventual failure.

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Lubricated equipment (cont’d)

 Procedure for re-greasing an anti-friction
bearing (roller) bearing mounted in a pillow
block with a purge plug
 Pull the grease plug
 Pump grease in until you no longer see old grease
coming out of plug hole. (I.E. when new grease begins
to come out)
 Run bearing for a couple of minutes to allow internal
pressure to escape.
 Stop bearing
 Put plug back in
 Restart bearing
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Lubricated equipment (cont’d)

 GEARS

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Lubricated equipment (cont’d)

 Purpose of Gearing
 Gearing is used to transmit power from a prime mover to
a final source with either an increase or decrease in
power or torque or a change in direction or plane from
that of the initial source.
 The driving gear is the pinion and the driven gear is the
bull

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Lubricated equipment (cont’d)

 Gears definitions
 Addendum - Area between pitch line and tip
 Bull - Driven Gear
 Burnishing - State of gear wear which leaves shiny
mirror-like finish on gear.
 Dedendum - Radial distance from pitch line to root
 Face - Surface area between pitch line to tip
 Featheredging - Gear wear mode resulting in metal
flow towards gear tooth.
 Flank - Surface area between pitch line and root.
 Galling - Gear wear resulting from lubricant failure.
 Interval of Approach - Time needed for gear
engagement.
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Lubricated equipment (cont’d)

 Gears definitions (cont’d)
 Misalignment - Gear wear from uneven load distribution
 Peening - Gear wear resulting in metal flow towards gear
end tips
 Pinion - Driving Gear
 Pitch Circle - Imaginary line of contact for outermost points
in gear circle.
 Pitting - Gear wear resulting in metal removal along pitch
line
 Root - Intermost region of gear tooth
 Scoring - Lateral gear wear along face and flank
 Scuffing - Lateral gear wear along gear face and flank
 Spalling - Severe pitting
 Tip - Outermost region of gear tooth
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Lubricated equipment (cont’d)

 Lubrication Factors to Consider in Gear Lube
Selection
 Gear type
 Gear speed
 Reduction ratio
 Operating Temperature
 Input power
 Surface finish
 Load characteristics
 Drive Type
 Application method
 Water Contamination
 Lubrication leakage
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Lubricated equipment (cont’d)

 Types of Gears
 Spur Gear - Gear set that generates with teeth that
run parallel to their mounting shaft. Low speeds/light
loads

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Lubricated equipment (cont’d)

 Types of Gears (cont’d)
 Bevel Gear - Gear set that operates in intersecting
shafts. Low Speeds

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Lubricated equipment (cont’d)

 Types of Gears (cont’d)
 Spiral Bevel Gear - Gear with intersecting shafts.
Carry more loads. Quieter/Smoother

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Lubricated equipment (cont’d)

 Types of Gears (cont’d)
 Helical - Gear with short line of contact. Load
distributed over more teeth at one time.

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Lubricated equipment (cont’d)

 Types of Gears (cont’d)
 Herringbone Gear - Gear that enables the opposing
thrust forces to be cancelled out. Parallel shafts.
Operate under shock and vibration loading.

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Lubricated equipment (cont’d)

 Types of Gears (cont’d)
 Hypoid Gear - Gear used when shafts must cross
but do not intersect. High speeds and moderate
loading

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Lubricated equipment (cont’d)

 Types of Gears (cont’d)
 Worm Gear - Gear set for large reduction ratios.
Compact with heavy load carrying ability. Produce
constant output speed and torque transfer.

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Lubricated equipment (cont’d)

 Characteristics of a Good Gear Lubricant
 Proper Viscosity
 Good Film Strength
 Good Rust Protection
 Good Oxidation Protection
 Good Demulsibility and Foam Resistance
 Good Anti-wear Properties

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Lubricated equipment (cont’d)

 Gear Box Lubrication possible disruptive points
 Gear wear
 Venting
 Operating temperature
 Leakage
 Excessive loads
 Contamination
 Lubricant

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Lubricated equipment (cont’d)

 Open Gear Lubrication possible disruptive
points
 Temperature
 Dirt
 Rust
 Water
 Method of application
 Disposal of waste oil

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Lubricated equipment (cont’d)

 Reasons Why Gear Sets Fail
 Surface Fatigue
 Wear & Scoring
 Plastic Flow
 Tooth Breakage
 Failure Associated with processing

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Objective 6 – Filtration process and

methods
 Reclamation and
conditioning of
lubricating oils are now
standard practices.
Lubricant conditioning
may be accomplished
by settling, centrifuging,
re-refining and filtering.
This topic will only cover
the filtration process
and methods.

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Filtration process and methods (cont’d)

 Filtering definitions
 Filtering - Removing microscopic solids in the range up
to 50 to 60 microns.
 Microns – 0.000039 in. or 0.000001 meter (linear
measurement)
 Straining – removing solids in size generally larger than
75 to 100 microns.
 Medium or element – the device that actually removes
and retains the solids or soluble impurities.
 Element particle – size rating; dimension in microns of
the particle that the element will retain to some
predetermined efficiency.
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Filtration process and methods (cont’d)

 Filtering definitions (cont’d)
 Element efficiency – ration of number of particles
removed to number present for any particular particle-
size rating.
 Influent – unfiltered portion of fluid.
 Effluent or filtrate – filtered portion of fluid.
 Absorb – depth filtration as contrasted to surface
retention.
 Adsorb – filter process performed by certain media
having the selective characteristic of retaining
undesirable solution impurities by an adhesive
phenomenon.
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Filtration process and methods (cont’d)

 Characteristics
 Pressure loss versus flow
 Particle size retention
 Pore size distribution
 Efficiency
 Dirt storage capacity
 Significant points
 Susceptibility of filter media to migration
 Channelling
 Rupturing
 Bypassing
 Action of various fluids
 Resistance to extraordinary temperature
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Filtration process and methods (cont’d)

 Filtration equipment
 Replaceable cartridge filters
 Bulk type filters
 Inert filters
 Adsorbent or active filters
 Extended area filters
 Edge type filters
 Wire wound filters
 Magnetic filters
 Web type filters
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Filtration process and methods (cont’d)

 Most mineral oil filters will be affected by water to

some degree.
 Filtration efficiency is impaired and flow rates
reduced thereby.
 If a filter is saturated thoroughly with oil before
water reaches it, it usually will shed considerable
amounts of water provided by flow rates,
viscosities, and pressures are not too high and the
water is not too finely divided or emulsified.

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Filtration process and methods (cont’d)

 Proper system design and operating procedures

leading to economical filtration can be obtained by
controlling or eliminating entry of contaminants into
a lubricating system.
 Every precaution should be used to minimize
entrance of water, dust, diluted fuel and other
foreign matter.

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Filtration process and methods (cont’d)

 There are three types of filtration systems in use

today:
 individual-machine continuous systems
 central-continuous systems
 central-reclaiming systems

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Filtration process and methods (cont’d)

 Central-continuous systems
 In high-production plants, central-continuous systems are
often used.
 In this method, used oil is pumped into a collecting line,
goes to a central-continuous clarification system and is
returned clean to the machines.
 Some operations require individual machine continuous
filtration, while in others, oil is used for several days,
taken to central-reclaiming plant, reconditioned and
returned to use.

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Filtration process and methods (cont’d)

 Hydraulically actuated machinery
 Hydraulic oils do not become contaminated in the same sense
as engine oils; nevertheless maintenance is required.
 Continuous filtration is the best way to maintain these oils in
the best condition, although intermittent filtration has proved
very successful.
 The proper filtration of hydraulic oils prevents excessive ware
of hydraulic parts, prevents clogging and sticking of control
valves and pistons and extends oil life.
 When straight mineral oils are used adsorbent filters are very
satisfactory.
 Inert filters are recommended for systems employing oils
containing oxidation and corrosion inhibitors and will maintain
these oils essentially free of abrasives.
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Filtration process and methods (cont’d)

 Synthetic fluids
 Synthetic fluids are sometimes used in place of
petroleum oils because of some shortcomings of
petroleum oils such as their inflammability and oxidation
characteristics.
 Filtration equipment for synthetic fluids varies with the
liquid. Both inert and active earth filters have proved very
satisfactory.

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Filtration process and methods (cont’d)

 Conclusion
 The trend in filtration is toward the removal of smaller
and smaller particles. It is generally found that the
filtration cost varies inversely with the size of the particle
retained.
 Continuous filtration is the most efficient and economical
way to operate. It is preferred over intermittent filtration or
batch filtration because contaminants are removed from
the lubricant as they are formed, thereby allowing the
engine or machine to operate on clean oil at all times.

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Filtration process and methods (cont’d)

 Conclusion (cont’d)
 Adsorbents are widely used in the conditioning
lubricating oil. The most commonly used adsorbent are
fuller‟s earth, acid-activated bentonites, bauxite, and
activated silicate.
 Centrifuges are extremely economical and simple to
operate, create no loss of additive content and occupy
very little space.
 The most important saving accruing from lube-oil
conditioning is in the extended useful life of the engine or
machine involved.

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Objective 7 – Best Practices &

Inspections

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Best Practices & Inspections (cont’d)

 Oil analysis/Cleanness

Oil analysis report example

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Best Practices & Inspections (cont’d)

 Lubricants must be kept cool, clean and dry
 All oil dispensing containers/equipment should be kept
clean
 No level of oil contamination is allowable
 All grease and oil drums, kegs and tanks should be
properly identified
 Proper „oil-house‟ rotation of lubricants is essential
 Lubricants have a shelf life
 Dust acts as an insulator - creates heat. Wipe dust
 Check oil reservoir ventilation and filter maintenance
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Objective 8 - Troubleshooting
 Circulating System problems:
 Low pressure
 High pressure
 Low flow
 High temperature
 Spray System problems:
 Lubrication does not occur
 Lube fault
 Farval System problems:
 Lubrication doesn‟t occur
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Objective 9 - Safety
 General speaking lubricants do not represent any
risk; however they should be properly handled,
stored and manipulated.
 Lubrication or hydraulic systems where high
temperature and pressure are present might
become a safety hazard, if a line, valve or seal fails.

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Safety (cont’d)
 General recommendations are:
 Piping, houses, seal, should be installed according to
operational conditions including possible extreme
conditions and a per government regulations.
 Safety switches (pressure, temperature, etc.) should be
operational and not jumped out.
 For lubricant handling and storage; using the proper
rigging and storing tools will greatly eliminate the risk of
accidents.

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Safety (cont’d)

Hoisting beam Drum handling cart

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Safety (cont’d)
 Cleanness: Oil spills represent an accident hazard.
Maintaining a clean and well organized area will prevent
accidents and will help to detect potential problems.

Lubricants Storing
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Safety (cont’d)
 Lubricants disposal:
Government
regulations should
always be followed
and the resources
provided for an
adequate waste
management.

Disposal system
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Lesson Review
 Define what friction is and how lubrication relates
to friction.

 A force that a body must overcome when slides across

another. Solid friction is present when two rigid bodies are in
contact and fluid when liquids or gases molecules are in
motion. Solid or sliding friction occurs mainly due to
asperities present in two surfaces that rub together. When
ever friction is overcome, moreover, dislocation of the
surface particles generates heat that could become
destructive. Additionally where there is solid friction, there is
wear; a loss of material due to the cutting action of opposite
asperities. Lubrication reduces or eliminate potential
equipment failure due to the friction action and also reduces
the power consumption by reducing friction between sliding
each other.
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Lesson Review
 Define what lubrication is and why it is important.

 The principle of supporting a sliding load on a friction-

reduction film is known as lubrication. Lubrication
reduces friction, prevents wear, removes heat and
prevents rust and corrosion.

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Lesson Review
 Describe the 3 main types of lubricants.
 Oils.
 Mineral: Consist of base oil and additives which
determine their performance characteristics
 Synthetic. Chemically synthesized (polymerization) and
designed to have specific properties.
 Industrial grease. Is a fine dispersion of an oil-
insoluble thickening agent, usually soap, in a fluid
lubricant which is generally mineral oil
 Solid Lubricants. There are may type of solid
lubricant used for different applications, like synthetic,
metallic or mineral powders.
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Lesson Review
 Describe the main lubricants properties.
 Mineral Oils  Industrial grease
 Oxidation stability  nature and amount of
 Anticorrosion properties thickener
 Wear protection  characteristic of mineral
oil
 Wetting behaviour
 whether additives are
 Viscosity-temperature behaviour used
 Synthetic oils  the way the grease is
 Low pour point and /or made


High flash / fire point and/or
High viscosity index and /or
 Solid Lubricants
 Oxidative and thermal stability
 synthetic
and /or  metallic

 High shear strength  mineral powders

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Lesson Review
 What are the advantages and disadvantages of
synthetic oil?

 These properties enable the lubricant to handle tougher

conditions (high temperature, temperature change,
water contamination, etc.) better that its equivalent
mineral oil, however due the high cost they are used
only under special conditions.

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Lesson Review
 Describe three types of oil lubrication systems.

 Oil bath
 Splash
 Circulating system
 Spray System
 Manually
 Central System (Farval)
 Details as per lubrication systems information.

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Lesson Review
 Describe what oil analysis is and its purpose.

 In the past the oil was changed only based on time, that is, in some
plants the oil was changed days or months after the last change
without any consideration of the oil condition. For mobile equipment
especially, the oil was changes based on miles or running time.
However today it is more common to find plants implementing oil
changes based on oil analysis. This procedure not only provides
information about the oil condition but also about the equipment
condition. Sometimes it can detect equipment problems even before
a vibration analysis would pick it up. The oil analysis provides
information in regards to the oil degradation, contaminants and metal
particles due to wear. It also helps to reduce lubricants consumption
costs and maintenance costs by preventing failures and repairing
equipment based on their condition rather that on a fixed time period.

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Lesson Review
 Name 3 problems related to the circulating system.

 Low pressure
 High pressure
 Low flow
 High temperature

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Lesson Review
 What are the main considerations when dealing
with hydraulic systems in regards to safety?
 Piping, houses, seal, should be installed according to
operational conditions including possible extreme conditions
and a per government regulations.
 Safety switches (pressure, temperature, etc.) should be
operational and not jumped out.
 For lubricant handling and storage; using the proper rigging
and storing tools will greatly eliminate the risk of accidents.
 Cleanness: Oil spills represent an accident hazard.
Maintaining a clean and well organized area will prevent
accidents and will help to detect potential problems.
 Lubricants disposal: Government regulations should always be
followed and the resources provided for an adequate waste
management.
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Lesson Review
 What are the two main categories of bearings?

 Plain
 Rolling element

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Lesson Review
 What is the purpose of gearing?

 Gearing is used to transmit power from a prime mover to

a final source with either an increase or decrease in
power or torque or a change in direction or plane from
that of the initial source.

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Lesson Review
 Name 3 oil additives.

 Antiwear agent (aw)

 Extreme pressure (ep)
 Oxidation inhibitors
 Detergent
 Dispersant
 Rust inhibitor
 Viscosity (vi) improver
 Pour point depressant
 Molybdenum disulfide
 Defoamant
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Lesson Review
 What are the components of grease?

 Oil
 Thickener
 Additives

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Lesson Review
 Name the 3 lubrication categories.

 Hydrodynamic lubrication
 Boundary lubrication
 Elastohydrodynamic lubrication (EHL)

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Lesson Review
 What is viscosity?

 Viscosity is defined as a measurement of a fluid‟s

resistance to flow.

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Lesson Review
 Name 3 type of oil filters.

 Replaceable cartridge filters

 Bulk type filters
 Inert filters
 Adsorbent or active filters
 Extended area filters
 Edge type filters
 Wire wound filters
 Magnetic filters
 Web type filters
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Lesson Review
 What is the most important saving obtained from oil
conditioning?

 The extended useful life of the engine or machine

involved.

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