Transcript SELECTING PERFORMANCE GREASE
SELECTING PERFORMANCE GREASE: Ten Crucial Questions Presented 4-13-2006 By Don Oldiges
Principles of Selection
Ten Crucial Questions Manufacturer recommendations Manufacturers usually provide a list of lubricants that meet the operating requirements for their equipment. (note that the equipment manufacturer's recommendation should not necessarily be considered the best selection.
Lubricant producer recommendations When manufacturers recommend lubricants for their products in terms of specifications or required qualities rather than particular brand names, lubricant producers should be consulted to obtain advice on products that comply with the required specifications.
User selection The user should follow the manufacturer's specification ensure that applicable criteria are met regardless of who makes the lubricant selection.
Ten Crucial Questions
Demands on Grease Performance
Challenging Environments Environmentally Friendly Temperature Extremes Heavy Loads High Speeds Long Life
Ten Crucial Questions
Performance Objectives of Grease
To remain in contact with moving surfaces and provide lubrication even under the stress of gravity, centrifugal action or pressure.
To retain its properties under use conditions at all levels of shear and temperature.
While performing the above, the grease must still be able to flow or be pumped where it is needed.
Ten Crucial Questions
1: Know When to Use Grease
Applications suitable for performance grease .
Machinery that is idle for long periods.
Moving parts that are “Sealed for Life” Surfaces that are exposed to extreme conditions.
Extending the life of worn components.
Functional Properties
Sealant to minimize leakage Sealant to minimize contamination Rigidity holds it in place where its needed Holds finely ground solid lubricants like moly or teflon.
Ten Crucial Questions
2: Know the Types of Grease
Grease is classified by penetration number and by type of soap or other thickener.
Aluminum, conventional Aluminum, complex Calcium, conventional Calcium, anhydrous Calcium, complex Lithium, conventional Lithium, complex Polyurea Organo-clay Silicone
What is Grease?
Grease Ten Crucial Questions Antioxidant Antiwear Antirust Anticorrosion Extreme pressure VI Improver Tackifier Pour Point Depressant Solid Boundary Lubricants Dye Soap Lithium, Sodium, Barium, Calcium, Aluminum Non-Soap (inorganic) Clay, Graphite, Silica Carbon Black Non-Soap (organic) Polyurea, PTFE, Wax Petroleum Oils Polyalpha Olefins (PAO) Polybutenes Esters Polyglycols Polyethers Silicones PFPE
Ten Crucial Questions
Grease Compatibility Chart
All greases are not created equal, caution must be exercised when replacing or refilling a grease.
Aluminum Complex Barium Calcium Calcium 12-Hydroxy Calcium Complex Clay Lithium Lithium 12-Hydroxy Lithium Complex Polyurea C I I C I I B B C B I I I I I I I C I C I I C C I C C B C I C C C C B C C C C I I I I I I C C I C C C = Usually compatible. B = Borderline compatibility (probably incompatible).
I = Incompatible I I C C I C I I I I B I C C I I C C C I B I B C I I C C C I C I C C C I C C C I B I I I C I I I I C
Ten Crucial Questions
What Do Most People Use?
Li Complex 15% Li Conventional 53%
2004 Global Production per NLGI Survey
Ten Crucial Questions
3: Know your Classifications
Professional societies and organizations have established classifications for oil and grease. The most widely encountered are those of the following organizations:
SAE (Society of Automotive Engineers) API (American Petroleum Institute) AGMA (American Gear Manufacturers Association), ISO (International Standards Organization) NLGI (National Lubricating Grease Institute).
Ten Crucial Questions
NLGI grease classification
000
NLGI Number
1 2 00 0 3 4 5 6
ASTM Worked Penetration
445 - 475 400 - 430 355 – 385 310 – 340 265 – 295 220 – 250 175 – 205 130 – 160 85 - 115
Consistency
Semi-fluid (Ketchup) Semi-fluid (Applesauce) Very soft (Deli Mustard) Soft (Tomato Paste) Common Grease (Peanut Butter) Semi-hard (Solid Shortening) Hard (Frozen Yogurt) Very Hard (Hard Butter) Solid (Brick Cheddar Cheese)
Ten Crucial Questions 4: Know the Typical Performance Properties of Each type of Grease
Aluminum, conventional Aluminum, complex Calcium, conventional Calcium, anhydrous Calcium, complex Lithium, conventional Lithium, complex Polyurea Organo-clay Sodium 175 350 200 230 350 275 350 350 350 350
Excellent Good Fair Poor
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5: Know Any Special Requirements
Special Performance Requirements
Federal Specs and Standards
Mil Specs and Standards
Food Grade Specifications
ISO Standards
ASTM Specifications EXAMPLES MIL-G-3545
High Temperature Grease
MIL-G-4343B
Grease, Pneumatic System
MIL-G-7711
General Purpose EP Grease
MIL-G-18458
Wire Rope Grease
MIL-G-21164C
Grease, Moly Disulfide
MIL-G-25760
Synthetic Grease
MIL-G-46886
Soluble Oils Silicone Grease
Ten Crucial Questions 6: Know the Grease Characteristics Required for the Application Apparent Viscosity
(non-Newtonian)
Bleeding, Migration, Oil Separation Consistency, Penetration, NLGI Numbers Corrosion, Rust and Water Resistance Dropping Point Evaporation Oxidation Stability Pumpability Shear Stability Temperature effects Pressure Effects
Typical Grease Tests
Ten Crucial Questions
Test
Cone Penetration Dropping Point Apparent Viscosity 4 Ball Wear Evaporation Copper Corrosion Water Washout Rust Resistance Oxidation Stability
ASTM Method
D-217 D-2265 D-1092 D-2266 D-972 D-4048 D-1264 D-1743 D-942
Test Description
Depth a “cone” pushes into grease Temperature where grease “melts” “Thickness” of grease Apply load until balls weld Weight loss from grease Chemical reactivity with metal Removal of grease by water Protection of iron & steels Storage stability
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Common Test Equipment
Penetrometer Grease Worker
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What is Penetration?
ASTM D-217
Penetration with respect to a lubricating grease, is the depth (in tenths of a millimeter) that a standard cone penetrates a sample of the grease under prescribed conditions of weight, time, and temperature.
Penetration is a measure of consistency of a grease to determine its plasticity.
Ten Crucial Questions Grease Shear Stability Motor-Matic Grease Worker Test
ASTM D-217-A
Shear or mechanical stability of a grease is its ability to withstand repeated working with minimum change in its structure or stability.
The shearing action in the test apparatus simulates the working of the grease in service.
The consistency is measured after 60 strokes and repeated after 10,000 or more strokes.
Ten Crucial Questions
Four Ball EP Test
ASTM D-2783
The test is the determination of the load-carrying capacity of a lubricant in kilograms applied to a system of four steel balls in the form of a tetrahedron.
The results are used to evaluate the EP characteristic of the lubricant by a load scar curve and weld point.
The procedure consists of a series of 10-second runs made at pre selected and successively higher loads until the welding of the four balls occurs.
Ten Crucial Questions Simple Rotational Viscometer ("Brookfield type") This device measures fluid viscosity at fixed rotation speeds by driving a measurement tool ("spindle"), immersed in the test fluid, through a calibrated torsion spring.
Viscous
drag of the fluid against the spindle causes the spring to deflect, and this deflection is correlated with torque. The calculated
shear rate
depends on the rotation speed, the tool geometry, and the size and shape of the sample container. Conversion factors are needed to calculate viscosity from the measured torque, and are typically pre-calibrated for specific tool and container geometries.
Viscosity Grade Comparisons
Kinematic Viscosity cSt @ 40 °C 2,000 Saybolt Viscosity Universal Seconds @ 100 °F 10,000 1,000 500 5,000 3,000 2,000 300 200 100 50 30 20 10 ISO/ASTM Viscosity AGMA Grades SAE Crank Case Oils SAE Gear Oil 100 60 1,000 500 300 200
Ten Crucial Questions
Ten Crucial Questions
7: Know how the Grease is Applied
Automatic lubricating systems Pressure Injectors Metering pump Hand operated grease applicator Cartridge Grease Gun Grease Filler Pump Brush
Ten Crucial Questions Example of a Large Automatic Lube Application System
Ten Crucial Questions 8: Know the Packaging Required & Available
Small Containers Cartridges Aerosols Pails Drums or Totes
Ten Crucial Questions 9: Know the Marketing/Supply Channel
Where do I go to get “Good” grease?
Performance Grease SUPPLIER
GREASE MAKER DISTRIBUTOR PRIVATE LABELER CO-OP/ BUYING GROUP
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10: Know the Life Cycle Fate
Renewable & Safe Distribution Warehouse Consumer Packaged Grease Raw Materials
Performance Grease
Disposal Environmentally Responsible
QUESTIONS???
Ten Crucial Questions
Ten Crucial Questions
Ten Crucial Questions
Anhydrous Calcium Grease
Bentonite Clay Grease
Ten Crucial Questions
Ten Crucial Questions
Calcium Complex Grease
Ten Crucial Questions
Lithium Complex Grease
Ten Crucial Questions
Lithium 12-Hydroxy Grease
Ten Crucial Questions
Aluminum Complex Grease
Silicone Grease
Ten Crucial Questions
Fluorosilicone Grease
Ten Crucial Questions
Polyurea Grease
Ten Crucial Questions
Fatty Acids for Grease
Ten Crucial Questions
Grease Reactions
Ten Crucial Questions
Trimer Reaction
Ten Crucial Questions
PAO 4
Ten Crucial Questions
PAO 40
Ten Crucial Questions
Ten Crucial Questions