The correct lubricant

Additional information and illustrations (Petr Vavruch does not always agree with all the views expressed in these web sites)

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The next two day  workshopscheduled in South Africa in 2018:

Area Start date End date Bookings closure
Cape Town 12 September 2018 13 September 2018 31 August 2018

The first workshop in 2018, positively evaluated by all participants, was held in Benoni, East Rand, Gauteng on 14-15 March.


To say lubrication is important is an understatement. The role of lubrication in reducing friction, cooling, minimising wear, improving efficiency and avoiding unplanned downtime is as critical as the design or componentry of any machinery.
Aaron Stone


Chevron Oronite OLOA 61530 - no API or ACEA mentioned (9 July 2018)
Lubrizol launches mid-SAPS lubricant additive for ACEA 2016 (11 June 2018)
Should older API engine oil categories be on the chopping block? (5 June 2018)
GE exits locomotive business, sells division to Wabtec (28 May 2018)
Chinese firm to become the world's largest producer of lithium? (25 May 2018)
Volvo next generation requirements (23 May 2018)
A more affordable tribometer test (22 May 2018)
API invokes provisional licensing for API CK-4 and API FA-4 (10 May 2018)
SN Plus (30 April 2018)
SN Plus licensing begins (25 April 2018)
ACEA specification update (11 April 2018)
Toyota recommends SAE 0W-16 (4 April 2018)
KH Neochem plans refrigeration oil additives plant (5 January 2018) "Additives"?
Engen to sell retail assets in 10 African countries to Vivo Energy in share swap deal (8 December 2017)
API announces plans for SN Plus in donut (17 October 2017)
GF-6 timing may come down to key test (11 October 2017)
Glencore confirms acquisition of Chevron’s South African and Botswana assets (9 October 2017)
Base stock update (6 September 2017)
Mazda Motor to launch world’s first commercial gasoline engine to use compression ignition (9 August 2017)

Graphene, a recently discovered material, is defined as a form of elemental carbon composed of a single flat sheet of carbon atoms arranged in a repeating hexagonal lattice. This lacy, honeycomb-like sheet of carbon atoms — essentially the most microscopic shaving of pencil lead you can imagine — is not just the thinnest material known in the world, but also incredibly light and flexible, hundreds of times stronger than steel, and more electrically conductive than copper.

The latest research interacts (a) molybdenum disulphide with nano-diamond particles on one surface and (b) a diamond-like carbon (DLC) surface on a ball to determine if superlubricity could be detected in a similar manner to graphene. It works by breaking moly and creating a onion-like carbon structure.


Lubrication - general
1. Three basic aspects of lubricating oils
1.1 Viscosity, kinematic, dynamic, ISO VG
1.2 and 1.3 Viscosity of engine oils and automotive gear oils, SAE, multi-grade
1.4 Viscosity index, viscosity modifiers, viscosity-temperature chart, calculators
1.5 Pour point, pour point depressant
1.6 Flash point and Noack volatility
1.7 Charts, blending
Answers to 1.7 (link)
1.8 Foam, entrained air and air release, defoamant
1.9 Base stocks, saturates, aromatic hydrocarbons, API groups
Vegetable oils and biodegradable lubricants
1.9.1 What does 'synthetic' mean?
Synthetics - usage
1.9.2 Polyalphaolefins (PAO)
Food-grade lubricants
1.9.3 Other synthetic hydrocarbons
1.9.5 Polyalkylene glycols (PAG) (polar compounds)
1.9.6 Esters and amides
1.9.7 Naphthenics
1.10 Oil performance, performance additives
1.11 Water separability (demulsibility)
1.12 Supplemental ('proprietary') additives
2. Answers to REVISION 1 (link)
3.1 Engine oils, detergents, dispersants, ZDDP, fuel economy
Friction and wear
Sludge, drain intervals, maintenance
3.2 Engine oil specifications, API service categories
3.3 and 3.4 Sulphated ash, TBN
3.5 ILSAC (International Lubricant Standardization and Approval Committee)
3.6 ACEA (Association des Constructeurs Européens d'Automobiles) and Equipment Manufacturers (OEM)
3.9 Two-stroke petrol engines
3.10 Outboard motor oils
3.11 Motorcycle oils
3.12 Gas engines
3.13 Marine engines and emergency power generation
3.15 Gas turbines
3.16 Automotive gear oils for manual gearboxes
3.17 Limited slip differentials
3.18 and 3.19 Eaton (form. Fuller) and ZF-FreedomLine, Caterpillar
3.20 Allison
3.21 Total Acid Number (TAN)
3.22 Automatic transmission fluids (ATF)
3.23 Farm equipment oils, UTTO, STOU
3.24 Brake fluids
4. Answers to REVISION 2 (link)
5. Lubrication conditions, EHL, anti-wear, EP
6. Industrial gear oils
Micro-pitting, wind turbines and using synthetics in gears
6.1 Worm gears (PAG)
6.3 Open gears
Gear failures
Chain and wire rope lubrication
7. Greases (also 7.3, 7.5 and 7.7)
7.1 and 7.2 Grease thickeners, polymers and compatibility
7.4 Grease lubricated rolling element bearings
7.6 Grease-filled gearboxes
7.8 Grease or oil?
8. Bearings (also 8.2)
Extreme applications - spindle oils, sugar mills, Morgan and Danieli
8.1 Rolling element bearings
Rolling element bearing failures
8.4 Steam turbines, varnish
9.1 Air compressors, coalescer filters
9.2 Vacuum pumps
9.3 Compressors for other gases
9.4 Refrigeration compressors
10. Hydraulic fluids
10.1 Fire-resistant fluids
10.2 Oil cleanliness
Particle counting, cleaning oil, filtration
Oil filters
11. and 13. Lubricant storage and storage life (shelf life)
12. Transformer oils
14. Machine tools
15. Cutting fluids, metal cutting, grinding
16. Rust preventives
17. Answers to REVISION 3 (link)
Hint No. 2 for CHALLENGE (link)
Hint No. 3 for CHALLENGE (link)
18. CHALLENGE solution (pdf)
Answers to questions (link)
Oil suppliers' information, approved and recommended lubricants (for information only)
Maintenance, lubricant monitoring, sampling and analysis (in the following sections)
Monitoring equipment without special instruments and without laboratory samples
Designing oil analysis programme, condition monitoring, standard test methods
Oil and grease sampling
Sampling frequencies
Maintenance strategies - reactive, preventive, predictive and proactive
Internet of things (IoT)
Root causes of failures, advanced test methods
Analysis interpretation, grease analysis
Water contamination
Management, maintenance management, lubrication excellence
Training, education, skills
Light reading

"Machinery Condition Monitoring: Principles and Practices": In machinery condition monitoring, a decision on the condition of a machine is dependent on the nature of its signals. For example, if the machine produces excessive noise and vibration, one gets a clue that something is not normal with the machine. These signals are usually time varying and need to be understood because they carry the information from the machine to the decision system, which can be a developed software or a person.

Lubrication - general

Top 10 things you (maybe) didn’t know about lubrication (20´ video, 2015)
Lubricants, Tribology
Dr. Gamini Amarasekera - Overview of lubricant technology (2010)
Lubrication basics
Afton - Basics of lubrication (video 10:47)
Principles of lubrication (sample video)
Lubrication and beyond (brief)
Lubricant fundamentals Part 1 (video 13:42)
Lubricant fundamentals Part 2 (video, additive introduction is in Part 1)
How lubricants work I (video 4:44)
How lubricants work II (video 6:43)
Avoiding metal-on-metal surface contact
Lubrication and greasing: working principle (brief)
Overcoming the most common lubrication misconceptions
Short videos by Noria
Lubricant specifications (in general, 2016)
Acculube - Tech talks
Machinery Lubrication - Tips and articles (2017)
Tribonet - How lubricants work (short video)
Compressionjobs - Lubrication of machinery
What's hot? Current trends in lubrication and oil analysis
Ten hot lubrication trends
Maintaining lube oil quality (2009)
Noria - How to extend oil life (short video 2017)
Klüber articles, e.g. Bearing lubricating procedures
Lubrita - References
Rexnord - Library
STLE - Archive
TESTOIL - Knowledge center
UE - Lubrication resources and information
Various lubrication systems (2016)
General Petroleum - Various classifications
Cepsa - Glossary
TESTOIL - Glossary
Glossary of terms
Oil industry abbreviations
Afton - Acronym glossary
Infineum - Acronym glossary
Engineers Edge
Westmoor - European Lubricants Coding: ISO 6743
Chevron Marine - Technical bulletins
Croda literature
KEW Engineering - Articles
Power Transmission Engineering - Articles
Machinery Lubrication - Articles
Machinery Lubrication - Subscribe
Oil specifications - Articles, references
Precision lubrication - Articles
Trico Corp. - Articles
The Five Rights of lubrication
Are you using the wrong oil?
Why oil goes bad
Five common lubrication problems and how to fix them
The 100 failure modes of lubrication and lubrication programs (2014)
2004 List of interchangeable lubricants
A Q&A guideline for purchasing lubricants (2007)
Selecting the right lubricant supplier
Purchasing lubricants based on performance
Effects of lubricants mixing in a machine
TESTOIL - Lubricant compatibility testing (webinar)
DES-CASE - The downstream effect of lubricant contamination and the value in controlling it (video)
The hidden dangers of lubricant starvation
Mobil - Using UV dye for leak detection
Lubricant toxicity (2016)
Efunda - Seal material compatibility
Seal material compatibility
Parco - Elastomer selection tool
Timken - Guidelines for bearing seals
Advantages of labyrinth seals
How to mitigate contaminant ingression in hydraulic systems (2017)
Best practices for waste oil management
Reclaim and recycle used oil (2015)

In the lubrication industry it is pretty common to have heard of or experienced a lubrication issue due to mixing of incompatible lubricants. Issues encountered include excessive foaming, formation of precipitates or deposits and loss of key performance characteristics such as water separability. Given the gravity of the impact on machine reliability that these issues can cause, there is a demand for testing that can help predict if mixing two lubricants might result in operational issues. Although the lubricants may be deemed equivalent or comparable, that does not mean they are compatible.

Are you having machine failures? Most companies are now realizing that maintaining clean oil is one of the best investments they can make, with contamination at the core of premature machinery failure and diminished lubricant life. A desiccant breather can be used as a first line of defence in preventing contaminants from ruining your equipment.

1. Three basic aspects of lubricating oils

What is lubrication?
Lubrication basics
Wikipedia - Lubricant
MRG Labs - Laboratory Lubricant Analyst training (LLA-I) clip
Effects of using a wrong lubricant
Viscosity starved machines (2015)
David Wedlock - Uninhibited base oils (2017)
Oxidation (TOST) test description (Shell Tellus S)
How oxidation occurs (short video)
Dr. Robert M. Gresham - Antioxidants (2018)
Vincent BOUILLON, BfB Oil Research - Overview of oxidation laboratory tests on industrial lubricants (first published in Lubes magazine, 2017, 1.3 MB)
Oxidation test RBOT
Schaeffer's - Oxidation and new requirements for Heavy-Duty Diesel (HDD) oils (2017)
Rust and corrosion
Inhibiting rust and corrosion to prevent machine failures

Some antioxidants, such as butyl hydroxy toluene (BHT), will turn oil bright red when oxidizing during normal service. While not always cause for alarm, it is clear evidence that the antioxidant is depleting.

1.1 Viscosity, kinematic, dynamic, ISO VG

Parker Kittiwake - Viscosity: A lubricant’s most important characteristic
LE - Viscosity
Oelcheck - Viscosity
Synlube - Viscosity
TLT - Viscosity and types of fluids (2017)
Oil viscosity, how it's measured and reported
Cannon Instrument - Measuring viscosity of industrial and engine oils (one page, 2017
Understanding absolute and kinematic viscosity
ISO VG limits
Noria - ISO VG limits
Industrial lubricants (incl. Viscosity Guides)
Roymech - Viscosity theory
Viscosity, temperature and pressure
Viscosity too high, too much lubricant (short video)
Affordable viscosity tester
Parker Kittiwake - Heated viscometer
Spectro - Portable kinematic viscometers

Viscosity is a fluid's characteristic demonstrating its resistance to flow. By definition, unit of dynamic ("absolute") viscosity is the poise, which is defined as the force in dynes required to move a surface one square centimetre in area past a parallel surface at a speed of one centimetre per second, with the surfaces separated by a fluid film one centimetre thick. We commonly use the centipoise (cP) and for kinematic viscosity the centistoke (cSt). There are other methods for determining viscosity, including Saybolt Universal Viscosity (SUV), Saybolt Furol viscosity, Engler viscosity, and Redwood viscosity. Since viscosity varies inversely with temperature, its value is meaningless until the temperature at which it is determined is reported. Viscosity can increase by oxidation and can be reduced by heating through thermal cracking.

1.2 and 1.3 Viscosity of engine oils and automotive gear oils, SAE, multi-grade

Lubricant must perform and properly flow, even at the coldest temperatures (2018)
Lubrizol - High temperature high shear viscosity test
SAE adds two new grades SAE 8 and 12 to J300
SAE adds light engine oils categories
Ultra-low viscosity engine oils - Go to page 26
Widman - SAE J306 Viscosity classification for Automotive gear oils
Early discussion about new SAE grades
Japanese race to reduce viscosity

A small increase in lubricant viscosity may be due to the volatilization of base oil "lighter ends" after prolonged high-level operation (i.e. the lubricant has become "thicker"). Significant increases in viscosity up to 20 percent are regarded as severe, caused by incorrect addition of a higher viscosity lubricant, extensive soot contamination and base oil oxidation.

1.4 Viscosity index, viscosity modifiers, viscosity-temperature chart, calculators

Wikipedia - Viscosity index
TLT - Viscosity index improvers (2011)
Don't ignore viscosity index
Viscosity modifiers: A fundamental study
Viscosity index improvers
Afton - HiTEC 5708A VI improver/Pour point depressant
Chevron Oronite OCP viscosity modifiers
Evonik - Viscosity modifiers
Evonik - VISCOPLEX VIIs for transmission fluids
Functional products viscosity modifiers
Infineum - Viscosity modifiers
Lubrizol - Viscosity modifier calculator
Widman - VI and viscosity calculators
A2 size nomogram for viscosity index

Applicable range: This graph is designed for viscosity indexes between 0 and 100, viscosity of 2-20 cSt at 100 °C, and 6.4-495 cSt at 40 °C. I will publish the wider range graphs (up to VI=200 and viscosity of 2-50 cSt) in near future.
Instruction: This graph has 12 graded lines for viscosity and one for viscosity index. Six lines are nominated for viscosity at 100 and six for 40 centigrade that are paired with letters A, B, C, D, E, and F. To start with the graph:
1. Determine the kinematic viscosity (in cSt) at 100 °C on one of the curved graphs and highlight it with a dot.
2. Determine its paired line using the letters bellow the graph.
3. Find the viscosity at 40 °C on its pair and highlight it with the second dot.
4. Draw a straight line with two dots and using a ruler, and extend it to right hand side to intercept the "Viscosity Index" line.
5. The VI is the interception point of these two lines. You can report it with ±1 accuracy.
6. If you have limitation to measure viscosity at 40 and 100 °C, use ASTM D341 to estimate them.
M. Mahdi Karima

ASTM D2270 - VI calculator
Calculator: Viscosity at operating temperature
Calculator: Viscosity at operating temperature
Calculator: Viscosity at operating temperature
Brendan Casey - Limits for hydraulic fluids

In 1929 Dean and Davis devised a system to express the viscosity/temperature relationship of an oil. The system, viscosity index (VI), was based on the viscosities of base oils obtained from a paraffinic Pennsylvanian crude oil, which was arbitrarily assigned a VI of 100, and base oils obtained from a naphthenic Gulf Coast crude oil, which was assigned a VI of 0.

1.5 Pour point, pour point depressant

Wikipedia - Pour_point
Engineers Edge - Pour_point
Noria - When to use an oil heater (2016)
Oronite - Pour_point depressants
Afton - Pour_point depressants (see video)
Evonik - Pour_point depressants
Oil gelation (2016)

1.6 Flash point and Noack volatility

Wikipedia - Flash_point
Noack_volatility_test (but it is done at 250 °C !!)
Volatility of synthetic and mineral oils using TGA
Noack volatility test: a new set of upheavals (2018)

Volatility of engine oil lubricants in service has become of increasing concern to equipment manufacturers because of oil consumption, engine deposits and air pollution effects. Two types of methods are used to assess volatility: The first is based on simulated distillation by gas chromatography (GCD), and the second, Noack volatility, measures bulk oil weight loss after heating at a prescribed temperature/time.

1.7 Viscosity-temperature chart, blending

A proper viscosity-temperature chart
Various viscosity-temperature charts
Blending calculator
Widman - Mixing oils
Viscosities of base oil blends (spreadsheet)

1.8 Foam, entrained air and air release, defoamant

The polar nature of engine oil additives gives rise to their foam-stabilizing properties. The splashing action or the mechanical agitation, or both, of the crankcase oil during engine operation causes air and other vapors to be whipped around, resulting in foam generation. In extreme cases, the oil actually can be lost because of the foam. The entrainment of the air in the oil can also decrease the ability of the oil to provide an effective hydrodynamic lubricating film because of the air bubbles that compromise the integrity of the film.

Defoamants are typically polydimethyl siloxanes of various molecular weights and are only required at a few parts-per-million concentration to control lubricant foaming. It should be noted that the siloxanes are dispersed in the lubricant in the form of small particles or globules with specialized equipment. These small particles can be seen through the use of a phase contrast microscope similar to that used in clinical laboratories.

Cavitation is a violent condition typically in the suction of a pump leading to wear caused by air bubbles or water or oil vapour bubbles.

Is air a contaminant? (2008)
Foaming and air dispersions in industrial gear oils (2015)
Foaming and air entrainment (comment, 2018)
Controlling oil aeration and foam (brief)
Causes and solutions for foaming in oil (2008)
Air entrainment, foaming of hydraulic fluids
Cavitation or aeration? How to tell the difference (2017)
Foaming keeps coming up for discussion
Entrained air in hydraulic oil
How to control oil aeration (short video)

Return pipes into hydraulic reservoirs should be larger than the intake pipes and should end below the surface of the oil in the reservoir. Locate the return as far away from the suction as possible to allow the oil as much residence time as possible. Better still, install a baffle between the suction and discharge. Cut the return pipe at an angle so that it directs the flow toward the tank wall.


1.9 Base stocks, saturates, aromatic hydrocarbons, API groups

Automotive base oil presentation
Chapter in a book: The evolution of base oil technology
Chapter in a book: Base stocks
Base oils
Classification of lubricants
Understanding base oils
Understanding the differences in base oil groups
The fundamentals of mineral base oil refining
Group II base oils spreading (2017)
Chevron Group II base oils
Chevron Group II base oils for industrial oils
ExxonMobil base stocks
Consider base oil and refining method when selecting lubricants
GTL: Gas to liquids refining
GTL: Gas to liquids produces extremely pure base oils
Re-refining: Bringing used oil back to life
Chinese re-refining process (2017)
Arslan Enginery - Used oil recycling plant
Ergon - Bright stock alternative (VI = 81, 65% paraffinic)

Many of the benefits of high saturates Group II were discovered in use rather than being predicted, such as their much superior dispersant additive response in heavy-duty diesel applications.

Vegetable oils and biodegradable lubricants

(Beyond the scope of the book)
Biodegradable lubricants
Improving vegetable oil properties for lubrication
Biodegradable oils - How to apply and maintain
Controlling degradation in biodegradable greases
New test methods for lubricant biodegradability
Proposed ASTM biodegradable hydraulic fluid standard
What you should know about environmentally friendly lubricants

Silicone synthetic lubricants are used when resistance to oxidation, heat and/or water is important and the performance of other types of lubricants is unacceptable. Applications include high-temperature grease and the lubrication of oxygen compressors. Negatives for using silicone synthetics include high cost, poor boundary lubrication and poor additive solvency (they don't accept extreme-pressure and anti-wear additives).

1.9.1 What does 'synthetic' mean?

Oil base stocks (Mobil vs. Castrol on page 8)
What is a true 'fully synthetic' oil?

Synthetics - general

Petroleum-based mineral oils function very well as lubricants in 90 percent of industrial applications. However, they also have limitations depending on the type of base stock and additives used, the refining technology, and the operating conditions.

Conventional vs synthetic oil (short article, 2011)
Basics of synthetic oil technology
ExxonMobil synthetics (2015)
Chemours' Krytox - Perflouropolyethers (2017)
Benefits of perflouropolyethers
BASF - Hybrid high viscosity base stock
Methacrylates in combination with Group III in gear oils
Dow Corning - silicones (2017)

Synthetics - usage

SAIT - Financial benefits of synthetic lubricating fluids (2016)
AAA report lauds synthetic oils
AAA report (2017, informative)
How true are the performance claims of synthetic engine oils? (2017)
Basics: When to use a synthetic gear oil
Guidelines for selecting high-temperature lubricants
Synthetic gear oils
Choosing between synthetic lubricants and conventional oils
Advantages of synthetic base oils (2018)
Is synthetic motor oil better for your car? (7 minute video - Answer: Yes)
When does synthetic oil make sense? (short video)
Is synthetic oil better?
Are synthetic lubricants really that good?
PAO-based lubes make machines run cooler (2017)
Are synthetic lubricants always a wise choice?
KEW Engineering - Mineral or synthetic? - Scroll down
Selecting oils with high pressure-viscosity coefficient and increase bearing life
LE - When do synthetic lubricants make sense?
Synthetic lubricants for automotive components
Micro-pitting, wind turbines and using synthetics in gears (links)

Synthetic oils have better resistance to ageing and a longer service life, the time between oil changes could be three to five times that of mineral oils. Synthetic oils have improved thermal and oxidation resistance, improved viscosity/temperature characteristics, better low temperature properties and lower evaporation properties. In some instances, synthetic oils have less tendency to form residues.

PAOs have inherently higher specific heats, so it will absorb more heat allowing the PAO-based lubes and the parts that they lubricate to run cooler.

1.9.2 Polyalphaolefins (PAO)

ExxonMobil - Group IV Basestocks: Polyalphaolefins (PAO)
AMSOIL - All synthetics are not created equal
Dodecene-based Synfluid PAOs
Synfluid mPAOs
Mobil 1: True PAO-based synthetic oil
Mobil SHC industrial lubricants (video)
ExxonMobil synthetic fluids and lubricant base stocks
ExxonMobil - Group IV base stocks: PAO
Mobilgear SHC XMP 320 in wind turbines

Food-grade lubricants

(Beyond the scope of the book)
Food-grade lubricants
Advantages of food-grade lubricants
NSF certified 'food-grade' lubricants
MOSH and MOAH dangerous?
ELGI - The selection and usage of food safe lubricants
Lubriplate - The continuing evolution of food grade lubricants
Lubriplate - H-1/Food grade lubricants
PAG food-grade lubricants
SKF introduces food-grade lubricants
Evonik - Viscoplex 8-219 VI improver for hydraulic fluids registered by InS Services as HX-1 ingredient for H1 lubricants with incidental food contact

1.9.3 Other synthetic hydrocarbons

Alkyl benzene as a compressor lubricant
Alkylated naphthalenes
King Industries - Alkylated naphthalenes (2017)
TPC Group - Polyisobutylene
BASF - Polyisobutylene

1.9.5 Polyalkylene glycols (PAG) (polar compounds)

PAG synthetic oil
Polyalkylene glycols
Polyglycols for lubricating large gear drives
Polyalkylene glycol - synthetic turbine fluid technology
Turbine lubricants: biodegradable, preventative alternatives
Synthetic gear oil selection - See wear of aluminium components
New synthetic OSPs for high performance greases
Klüber: Changeover from mineral oil/polyalphaolefin to polyalkylene glycol
Ucon OSP - oil soluble PAG
Oil soluble synthetic polyalkylene glycols
Innovations in PAG based lubricants
Energy efficient industrial gear lubricants
Sullube - Laboratory analysis of PAG in service
Heat of combustion, flash point, autoignition temperature of PAG
Effects of water on PAG
Removing water from PAG
Worm gears (links)

Sludge and varnish in hydraulic controls of turbines is not a problem with PAG turbine oils owing to their high solubility. However, some PAG turbine oils cause sudden oxidative degradation, resulting from a decrease in anti-oxidants due to poor thermal stability of those PAG base oils.

1.9.6 Esters and amides

Schaefer - Esters in synthetic lubricants
Schaefer - Esters in synthetic lubricants
Synthetic esters
Inolex - White papers on esters
Wikipedia - Polyol esters
Rexroth - List of environmentally acceptable hydraulic fluids
Biodegradable lubricants (links)
Croda Lubricants to launch new Group V base oil technology (amides)
Emery Biolubricants (Esters)
Environmentally friendly lubes for marine use (2017)
Natural ester oil application in liquid filled transformers (2.5 Mb)

1.9.7 Naphthenics

Nynas - Base oil handbook
Nynas - Group I replacement with naphthenics
Nynas - Naphthenic oils for greater efficiency
Nynas - Anti-oxidant response of low sulphur naphthenic base oils (2017)

1.10 Oil performance, performance additives

Additives in lubricating oils
The chemistry and function of lubricant additives (2017)
The contributions of additives
Lubrizol - Lubricant fundamentals 2: additives (video, introduction in end Part 1)
Formulations of lubricating oils
Lubricant additives
Infineum - Additives (2017)
The truth about additive depletion (video)
The critical role of additives in lubrication
How to determine the quality of a lubricant additive
Rhein Chemie additives

Neither mineral nor synthetic base oils can satisfy today’s lubricant performance requirements without using additives. Additives are chemical substances, in most part synthetic, which are used in lubricant formulations to adjust a broad of spectrum of properties by enhancing what is desired and suppressing what is unwanted. Many additives are multifunctional products that may exhibit synergistic or antagonistic behavior when mixed together. As a rule of thumb, additives do not add. This makes balancing and optimization of additive systems a challenging task.

1.11 Water separability (demulsibility)

The importance of demulsibility in oil
TESTOIL - Demulsibility
Water separability
Test Method for Water Separability
Demulsibility ASTM D 2711

1.12 Supplemental ('proprietary') additives

Advice for improving oil with additives
The disadvantages of using anti-friction metal conditioners
The advantages of lubricant conditioners
How engine cleaners affect your oil

Blue exhaust smoke indicates an engine is headed for serious mechanical failure due to a high oil ingress into a combustion chamber. This means an engine is burning too much oil due to worn intake valve guides or poor piston ring control – collapsed or worn rings.
A useful rough guide to measuring oil consumption is the ratio of oil consumption to fuel consumption, because the harder an engine works (fuel consumption) the more oil it will use. A good estimate is 0,6% of total fuel consumption.


Answers to REVISION 1 (link)

3.1 Engine oils, detergents, dispersants, ZDDP, fuel economy

Engine oil quality (2015)
Spectro Scientific - Webinar: Engines 101, Understanding basic engine operation
Engine oils
Lubrication system: Engine oil functions (video)
Selecting the correct lubricant
Wikipedia - Motor oil
Friction, lubricants, energy losses, tribo tests, engine oils, base oils, additives, coatings
Additives boost fuel economy
The anti-wear additive zinc dialkyldithiophosphate
Elco ZDDPs
Zinc phosphate reaction with iron oxide
History of ZDDP
BASF - IRGALUBE FE1 - Save fuel by interacting with ZDDP (2017)
Toyota - Better antioxidants, higher quality base oils to prevent turbocharger coking
New low viscosity grade engine oil specifications in Japan
Antifreeze contamination in motor oil (short video)

ZDDP reaction films formed on rubbing contacts produce enhanced friction in mixed lubrication conditions. The ZDDP reaction film appears to inhibit lubricant entrainment into the contact, thereby leading to a reduced EHD film thickness compared to ZDDP-free lubricants.

Turbocharged gasoline direct injection (TGDI) engines suffer from the presence of particulates in vehicle exhaust emissions, similar to a diesel engine. New oil specifications are needed to counter that.

Friction and wear

(Beyond the scope of the book)
Wikipedia - Friction
Castrol - Friction Reducing Technologies – Fact or 'Friction'
Friction and traction
Rolling friction
Friction theory
Droplet friction is similar to solid friction (2017)
How to reduce friction between surfaces
Friction modifiers
Friction modifiers (2015)
Superlubricity (2017)
Tribological design guide part 5: Wear theory
Wear theory
Researchers simulate wear of materials as they rub together (2016)
Basics of wear
Polishing-wear (2018)
Wear = the silent killer
Premature wear (short)
Three common contaminants and the oil analysis tests that can detect them
Nanopolishing for surface perfection
Basic wear modes in lubricated systems
Common causes of machine failures
Causes of engine bearing failure
Types of engine bearing damage
Main bearing failure chart
Bore glazing and polishing in diesel engines

Friction modifiers are most efficient under boundary conditions or where metal-to-metal contact occurs. Organic friction modifiers have long, soluble chains and a polar head. The polar head attaches to the metal surfaces. The soluble chains line up beside each other much like fibers in a carpet. The polar heads may be comprised of phosphoric or phosphonic acids, amines, amides or carboxylic acids. The soluble chains form dense mono layers or thick, reacted viscous layers. These layers shear easily and create a relatively slippery surface.

Corrosive wear occurs when a machine surface is damaged by chemical attack. The responsible corrosive chemical could be either vaporous or liquid, which might be found in a plant that mixes or handles strong acid or alkali materials. Often the damage to lubricated surfaces comes from acidic by-products generated by the deterioration of the lubricant.

Sludge, drain intervals, maintenance

(Beyond the scope of the book)
Engine oil sludge
Combating and removing engine oil sludge
Optimizing oil change intervals in heavy-duty vehicles
Extending oil change intervals on heavy mining equipment
Extending preventive maintenance (PM) intervals
Used-oil analysis for predictive maintenance
Why predictive maintenance does not work
Proactive and predictive maintenance (links)
Cepsa - FAQ
FAQ after Noria webinar How to detect and control lubrication failure modes

Prof. Dr Boris Zhmud: Fresh engine oil (before it gets into the engine) normally has a cleanliness level in the range 16/xx to 18/xx. As soon as it gets into the engine, the cleanliness drops one-two levels because of mixing with the remaining old oil. An oil is "dirty" when cleanliness drops to 21/xx to 23/xx.

3.2 Engine oil specifications, API service categories

API Lubricants Group approves provisional licensing (30 June 2017)
Infineum - North American specification update (14 June 2017) Heavy duty tests scrutinized (2017)
Infineum - API Engine Oil Classifications (2017)
Engine oil specifications: Is the system broken?
API Engine Oil Service Categories
API Engine Oil Classifications
API Service Classifications
API licensing documents
API - Engine oil licensing
API - Engine oil licensing
API - Engine oil guide
API SN and SN-RC performance specifications
API Licenses
API pulls plug on ‘Energy Conserving’
API to discontinue licensing of 'Energy Conserving' oils for API SL and SM
New motor oils are bad for older engines (scroll down)
API base oil interchangeability
API guidelines for SAE viscosity grade engine testing
API certification system, 17th edition, Sept. 2012, 136 pages
The Sequence VIII test run on engine CLR L-38 ran out of bearings
Comparing gasoline and diesel engine oils

3.2 API service categories - diesel engine oils

API - Latest oil categories (2016)
API CK-4 and FA-4 is done
API approves CK-4 and FA-4 Diesel Engine Oil Categories
Chevron - API CK-4 and FA-4 explained
Shell - API CK-4 and FA-4 (promotional video)
Shell unveils CK-4, FA-4 strategy
Shell - Mobil Delvac 1300 Super 15W-40 does not meet API CK-4 nor Volvo, MACK and Cummins (2018)
ExxonMobil responds to Shell's claim that Mobil Delvac 1300 Super is not meeting API CK-4 (25 June 2018)
ExxonMobil's reply
Ford issues list of acceptable DEOs
Ford issues list of acceptable DEOs (2018)
API CK-4 and FA-4 licensed manufacturers (December 2016)
Cummins' CES 20086 and CES 20087 registered oils
Cummins' CES 20086 registered oils
Cummins' CES 20087 registered oils
Detroit Diesel - approved API CK-4 oils
Detroit Diesel - approved FA-4 oils
API CJ-4 performance specifications
Proposed ASTM standard to evaluate diesel engine oils in T-13 engines (2016)

API Service Category CK-4 describes oils for use in high-speed four-stroke diesel engines designed to meet 2017 model year on-highway and Tier 4 non-road exhaust emission standards as well as for previous model year diesel engines. These oils are formulated for use in all applications with diesel fuels ranging in sulphur content up to 500 ppm (0.05% by weight). However, the use of these oils with greater than 15 ppm (0.0015% by weight) sulphur fuel may impact exhaust after-treatment system durability and/or oil drain interval.
API CK-4 oils exceed the performance criteria of API CJ-4, CI-4 PLUS, CI-4, and CH-4 and can effectively lubricate engines calling for those API Service Categories - they are backward compatible.
API Service Category FA-4 describes certain XW-30 oils formulated for use in high-speed four-stroke diesel engines designed to meet 2017 model year on-highway and Tier 4 non-road exhaust emission standards with diesel fuel sulphur content up to 15 ppm (0.0015% by weight). Refer to individual engine manufacturer recommendations regarding suitability of API FA-4 oils.
API FA-4 oils are not interchangeable or backward compatible with API CK-4, CJ-4, CI-4 PLUS, CI-4, and CH-4 oils.
With the introduction of API CK-4 and API FA-4 diesel engine categories, Cummins developed two new standards, CES 20086 and CES 20087. Cummins has updated its CES 20086 list of API CK-4 registered oils, Cummins CES 20087 lists API FA-4 registered oils.

3.3 and 3.4 Sulphated ash, TBN

Prof. Dr Boris Zhmud - TBN (LUBE Magazine April 2018)
Low SAPS / low ash
TBN, oxidation and additives
Why an oil's base number (TBN) drops
Engine oils' BN (base number) and i-pH value
Measuring reserve alkalinity
Spectro - Measuring TAN and TBN

3.5 ILSAC (International Lubricant Standardization and Approval Committee)

Automakers ask API to update GF-5 now (26 July 2017)
Engine oil specifications: Is the system broken?
ILSAC GF-5 official
GF-5 performance requirements
Toyota Valve Train Wear Test ready for precision matrix testing
Lubrizol - Future ILSAC_GF-6 web site
Infineum - ILSAC_GF-6 web site
Lubrizol additive for SAE 0W-16

3.6 ACEA (Association des Constructeurs Européens d'Automobiles) and Equipment Manufacturers (OEM)

Europe base stocks and formulations (2018)
ACEA European oil sequences 2016
Infineum - ACEA 2016 brochure
AlterEvo Ltd blog 31.1.17 - ACEA 2016 Sequences
ACEA European oil sequences 2012
Lubrizol - ACEA European Oil Sequences 2012
Sarma - ACEA 2012 versus ACEA 2010 detailed comparison
European passenger car specifications
The ATIEL Code of Practice
ACEA Sequences: Combined claims guidance
Lubrizol - Relative performance tool
ACEA 2016 boosts oil performance
ACEA European oil sequences 2016
Infineum additives meet ACEA C5-16 requirements

In the M111 fuel economy test, ACEA C5-16 has a requirement set at 3.0% which is 0.5% higher than C2-16 at 2.5% and significantly higher than C3-16 at 1.0%.

3.9 Two-stroke petrol engines

Wikipedia - Two-stroke engine
Wikipedia - Two-stroke oil
Wikipedia - API TC
Wikipedia - JASO M345 standard
Dan's Motorcycle Repair Course - Two-stroke oil
Can using two stroke oil in a four stroke engine affect it?

3.10 Outboard motor oils

NMMA - TC-W3 Two-stroke oil certification program
Do I need TC-W3 engine oil?
NMMA issues its 2018 TC-W3, FC-W, and Catalyst Compatible FC-W certified oils lists
Understanding two-stroke engine oil

3.11 Motorcycle oils

Lubrizol - Motorcycle oils
Jaso oil specifications
New JASO T 903:2016 replaces the 2011 version for high friction (MA/MA1) and low friction (MB) oils
Jaso MA and Jaso MB classifications
Lubrizol - Jaso MA and MB
Lubrizol - Differences between Jaso MA and MB
What does Jaso MA2 mean? (Scroll down to discussion)
API SL and API SM formulations contradict Jaso-MA/MA1/MA2
Jaso updates four-stroke motorcycle specification
Lubrizol - Two-stroke motorcycle oils - Jaso M345 standard
Wikipedia - Jaso M345 standard
Motorcycles: Synthetic versus mineral oils
Motorcycle lubricant specifications lacking - Go to page 6
How to change your motorcycle oil (video)

Ducati calls for the chain to be cleaned and lubed every 1000 km. Also adjust your chain. Every time you clean, check the slack and adjust as needed.

3.12 Gas engines

Functions of oils in gas engines
Generation using gas-fuelled engines
Lubricating natural gas engines
Natural gas engine lubrication and oil analysis
Causes of nitration in engine oil
Gas engine oil analysis: what does the TAN/TBN crossover really mean?
Cummins issues new NGEO specification CES 20092 (2018)/a>

3.13 Marine engines and emergency power generation

Marine diesel engines
The Wärtsilä RT-flex96C, the world’s largest and most powerful diesel engine in the world today. Built in Finland, the RT-flex96C’s fourteen cylinders can deliver 80080 KW of power or enough to power an entire suburban town. The engine weighs 2,300 tons, stands 44-feet tall and is 90-feet long. In 2006, the Wärtsilä RT-flex96C engine was installed and finally set sail on the Emma Mærsk, a cargo ship that can carry 11,000 20-foot shipping containers at a breakneck speed of 31 knots.
Total Lubmarine launches Talusia Optima cylinder lube
Environmentally friendly lubes for marine use (2017)
Group II base oils in trunk piston engines (2017)

3.15 Gas turbines

Wikipedia - Gas turbines
AeroShell Turbine Oil 500
Mobil Jet Oil 387
Mobil Jet Oil 387 gets approvals from GE Aviation (2018)
Mobil Jet Oil 387 gets approvals for Rolls-Royce Trent 700, Trent 800, RB211-524 and RB211-535 engines (2016)
Mobil Jet Oil 387 gets approvals from Pratt & Whitney for TM 1500G engines (2017)
Mobil Jet Oil 387 gets approvals from Pratt & Whitney for PW1100G-JM and PW1400G-JM engines (2017)
Mobil Jet Oil 387 gains new approval with GP7200 engines (2017)

Ninety percent of lubrication professionals say a lack of attention has negatively impacted the reliability of equipment at their plant.

3.16 Automotive gear oils for manual gearboxes and final drives

Wikipedia - Gear oils
Widman - The difference between GL-4 and GL-5
Lubrizol - API GL-5
Manual transmission oils - is thinner really better?
A new level of performance: China GL-5 PLUS
ZF - Lists of lubricants
ZF has updated its lists of approved lubricants (2018)
Gear oil additive package Afton HiTEC 343
Magnetic plugs in dozer final drives
Used oil analysis determines the oil change interval in a big gearbox (2017)
Advances in manual transmission design and lubrication
How Haldex All Wheel Drive (AWD) works (video, 2017)

3.17 Limited slip differentials

Wikipedia - Limited slip differential
Castrol - Limited slip gear oil
Mobil - Limited slip gear oil
Doctoral theses: Wet clutch tribology - Friction characteristics in limited slip differentials

3.18 and 3.19 Eaton (form. Fuller) and ZF-FreedomLine, Caterpillar

Eaton Approved Lubricant Suppliers TCMT0020 EN-US, March 2015
Eaton revises its lubricant suppliers list (2018)
May 2018: Eaton lubricant suppliers list
Roadranger SAE 50 Synthetic Transmission Lubricant
Eaton - "Genuine Roadranger" and other lubricants
Cognis Emgard 2979 SAE 50
Cognis Emgard 2979 SAE 50
ZF-FreedomLine manual - select page 11
Caterpillar final drive and axle fluid requirements (2001)
Caterpillar revises its machine fluids recommendations bulletin (2017)
Caterpillar machine fluids recommendations (2017)
Barloworld - Caterpillar fluid specifications and recommendations

3.20 Allison

Allison transmissions - Click on Fluids
Allison fully automatic transmissions for road use
Allison vocational model guide
Allison oil analysis test recommendations

3.21 Total Acid Number (TAN)

Wikipedia - Total Acid Number
Oelcheck - NN (neutralisation number) or AN (acid number)
Acid number tests
Parker Kittiwake - General information regarding AN

3.22 Automatic transmission fluids (ATF)

Gearboxes and transmissions
How torque converters work (video)
Wikipedia - Automatic transmission fluid
Facts about automatic transmission fluids
Types of automatic transmission fluids
ATFs today, from ATF_ SURVEY_ REPORT_2017.pdf
ATF labels face a rewrite (26 July 2017)
Discussion: JASO-1A
Mobil's six automatic transmission fluids
Castrol automatic transmission fluids
Automatic transmission flushes (video)

3.23 Farm equipment oils, UTTO, STOU

Maintain a tractor
How to keep your tractor running (book)
Lubrizol - Universal tractor transmission oils
Lubrizol - Universal Tractor Transmission Oil (UTTO) additives
Fuchs TITAN UTTO - Also click AGRIFARM UTTO MP on the left
Caltex Super Tractor
Missouri retailers ordered to stop selling John Deere 303 (2017)

John Deere developed JD 303 in 1930 and replaced it 1974. Products making exclusive JD 303 claims can no longer be tested for compliance. JD 303 was replaced with J14-B, which was then replaced in 1978 with J20-A. John Deere has declared all of those specifications obsolete and has two current specs – JDM-J20-C and J20-D (which are backward compatible) – along with its genuine Hy-Gard fluid. Some lubricant marketers have continued marketing hydraulic tractor fluids labeled as meeting the 303 standard but critics say they do not meet the lubrication requirements of modern tractors and, in fact, can harm them.

3.24 Brake fluids

Wikipedia - Brake fluid


Answers to REVISION 2 (link)

5. Lubrication conditions, EHL, anti-wear, EP

Lubrizol - Lubricant fundamentals 1 (video)
States of lubrication
Wikipedia - Hydrodynamic lubrication
Lubrication regimes
Elastohydrodynamic Lubrication (EHL) theory
Timken - The right thickness of lubricant
How temperature impacts oil condition
The effects of temperature on lubricants (2007)
EHL with greases
How lubricants combat friction and wear
Friction modifiers
Friction modifiers (2015)
Wikipedia - Extreme Pressure (EP) additives
Dr Neil Canter - Extreme Pressure additives
The role of Extreme Pressure additives in gear oil
Limitations of EP additives
The effects of EP additives on worm gearboxes
The danger of EP additives on worm gearboxes (short video, 2018)
Elco extreme pressure additive
Solid-film lubricants
Wikipedia - Molybdenum disulphide
IMOA - Molybdenum sulphur compounds in lubrication
Climax Molybdenum - Molybdenum disulphide in lubricant applications
High temperature graphite bearing lubricant

At pressures above about 3000 psi (206 bar) there begins a significant increase in the viscosity of mineral oils. At 5000 psi (345 bar) the viscosity of a typical Group I base oil is approximately double its viscosity at atmospheric pressure. At higher pressures, the rate of viscosity increase accelerates and at very high pressures mineral oils cease to behave like liquids and tend to become waxy solids. Pressure viscosity coefficients are different for different types of oils, particularly for synthetic oils.

6. Industrial gear oils

Wikipedia - Gears
Industrial gear oils in 2016
Lubrication of gears
John Sander, LE - Selecting gear lubricants (pdf)
John Sander, LE - Selecting gear lubricants
Selecting the right industrial gear oil
Precision gear lubrication
Roymech - Gear lubrication
Trends in industrial gear oils (2008)
AMSOIL - DIN 51517 Part 3 (CLP) update (2010)
Klüber - Common industrial gear oil specifications (short)
Gear drive lubricants
Lubrication selection for enclosed gear drives
Trends in industrial gear oils
Maximising gearbox performance
FZG test description (Shell Tellus S)
LE - Improving gearbox lubrication by oil analysis condition monitoring, FZG machine
Gear lubrication - Gear protection also at low oil temperature
Troubleshooter’s guide to gear drives
Changing bad gear oil habits (2016)
Monitoring large particles in gear oils
Flushing methods (Solving recurring oxidation problems)
Articles by Lawrence G. Ludwig
GEAR Solutions - Articles
Xtek - Technical papers - select gear terminology
SPX Cooling Technologies - Evolution of cooling tower gearboxes (2018)
Improving anti-rust property of EP industrial gear oil (sale offer)
Vavruch and de Vaal - New industrial gear oil: focus on EP performance
Impact of gear tooth surface roughness and advanced coatings on effective gear tooth friction coefficient (2017)
SEW-Eurodrive - Equivalents - Pages 185-6
ExxonMobil - Energy efficient industrial gear lubricants (2013)
Lubrizol - Developing an energy-efficient industrial gear oil (2017)
Shell Omala grades
TOTAL gear oils
Idemitsu TDF continuously variable transmission oil
Lubricating with FlexGear
Grease-filled gearboxes (links)

Overfilling a gearbox sump can be just as damaging as underfilling. Overfilling may cause air entrainment and foam, overheated oil, and leakage due to overflow. Over time, oxidation may also occur due to increased temperatures and exposure to air.

Micro-pitting, wind turbines and using synthetics in gears

Stopping micropitting by using the right lubricant
Micropitting in wind turbines
Preventing micropitting and surface fatigue
Lubrizol - Meeting micropitting and materials compatibility challenges
Klüber - Synthetic gear oils (2018)
Klüber - Gear lubrication: Stopping micropitting
The effect of the surface roughness on micropitting
Proper lubrication is key to wind turbine longevity
Choosing the right wind turbine lubricant
Extending gear life with synthetic lubricants
Synthetic gear oil selection
Choosing between synthetic Lubricants and conventional oils
SAE - Traction coefficient measurement
Klüber - Lubricating gears with synthetic oils
Klüber - Specialty lubricants for optimum operation
Mobilgear SHC XMP 320 in wind turbines
Shell Omala S4 GX 680
Total Carter SH
Should you use synthetics? (links)

In addition to requiring oils to meet DIN 51517-3, Siemens MD requires an FVA 54 micro-pitting resistance test , dynamic foam testing and several stringent protocols for ensuring internal paint, elastomeric seal and liquid sealant compatibility.

6.1 Worm gears (PAG)

Worm gear lubrication
The right way to lubricate worm gears
Klüber - Improving energy efficiency with proper gear oils
Klüber - Gear oils based on polyglycols
PAGs perform better in worm gears
Reducing wear particle generation (filtering and using PAG)
Roymech - Worm gear theory
The ins and outs of worm gears
Worm gears, also Misaligned - Scroll down
Avoiding worm gear problems
The effects of EP additives on worm gearboxes
Limitations of EP additives
The danger of EP additives on worm gearboxes (short video, 2018)

6.3 Open gears

Lubrication of open gears
Lawrence G. Ludwig - Applying open gear lubricants (2009)
Philip de Vaal - Open gear lubrication
Shell Malleus GL 3500

Lower wear is achieved with spray lubrication compared to dip lubrication. Graphite is known to promote abrasive wear.

Gear failures

(Beyond the scope of the book)
Gear failures
Gear failure causes(short)
Analyzing gear failures (2012)
Analyzing gear failures (2001)
Recognizing gear failures
Bureau Veritas - Case study: Gear oil laboratory tests, water contamination (2017)

When receiving a new or reconditioned gearbox, open the drain plug and pump fresh oil through the system. This removes any contaminants that might not have been cleaned out during a rebuild or from a new machine. This will ensure your critical equipment has a better chance of reaching its life expectancy rather than coming to a grinding halt because of unforeseen contamination.

Chain and wire rope lubrication

(Beyond the scope of the book)
LE - Chain lubrication
Advice for chain lubrication
Lubrication of high-temperature chains
Improving oven chain lubrication
Rotalube chain lubricators
Lubricating wire ropes (short video)
Advice for lubricating wire ropes
Best lubrication methods for wire rope applications
Marine wire rope lubricator
Viper wire rope lubricator (video)
Viper wire rope lubricators

Grease life is not only determined by the operating conditions and bearing type. The grease type and grease quality are also very important. A good grease has a stable consistency, good shear stability, favourable bleeding and flow properties, and good boundary lubrication, including lubricity properties. The base oil viscosity should also be favourable for the speed and temperature.

7. Greases (also 7.3, 7.5 and 7.7)

Wikipedia - Grease
Grease basics
TLT - Grease manufacture (2017)
TESTOIL - Grease fundamentals and analysis (webinar)
Grease construction and function
Mobil - Grease: Its components and characteristics
Calculating grease quantity, frequency
Different types of grease
Chapter in a book: Greases
Understanding lubricants Part I
Discussing greases - Scroll up!
Shell - Presentation for the mining industry
Characteristics of grease

The bleeding rate, which is the bleeding per unit of time, should ideally somehow match the starvation rate. In the beginning of bearing operation, the lubricant film will be relatively thick and no additional feed of base oil is required. A too high bleeding rate will exhaust the grease at an early stage, leading to short grease life. If the bleeding rate is too low, the contacts will starve rapidly, leading to early damage.

SKF - Understanding grease technical data
Timken - Grease tests and limits --- and Commercial greases
Testing grease consistency with rheometer (2015)
Noria - Grease colour (short video)
Grease additives
Grease selection (2018)
Timken - Selecting greases
Consider consistency when selecting grease
Application is key in grease selection
Selecting a high temperature grease
Choosing a high-temperature lubricant
Choosing a high-speed grease
Biobased greases
Low-noise greases
Food-grade greases
Storing grease to avoid bleeding

grease guns
Anatomy of a grease gun
Grease gun best practices
What should we consider before purchasing a grease gun (short)
Grease guns
How to calibrate new grease guns (short)
The benefits of ultrasonic grease guns
Proactive lubrication - Ultrasonic grease guns
Grease thief for taking samples
Proactive maintenance (links)
UE - Bearing inspection and lubrication
Des-Case - Proper lubrication for greased bearings (Centralized application systems)
STLE - Grease volumes and frequencies
Machinery lubrication - Articles
TOTAL greases
Grease analysis (links)

When using automatic grease lubricators that are set for several months, draw a line and record the date at the level of the lube during each weekly inspection. This allows you to instantly spot a plugged or faulty lubricator.

Large, abrasive particles in grease may be more damaging than the same particles in oil because once the grease is applied, no opportunity exists for the contaminant particles to be removed; whereas in oil, the particles may be quickly removed by filtering. The particles in a grease sample may be scrutinized by dissolving the grease with a suitable solvent and then preparing a ferrogram. A mixture of toluene and hexane is effective at dissolving many commonly available greases.

Before installing grease into a new grease gun, consider disassembling the gun and cleaning it thoroughly. I have found metal shavings numerous times in different brands of new grease guns. The metal shavings appear to be from the manufacturing process of the grease gun. (John Flynn, RJ Reynolds Tobacco Co.)

7.1 and 7.2 Grease thickeners, polymers and compatibility

Why certain greases are more popular
Castrol - Grease thickeners
Choosing a multi-purpose grease: Lithium complex or calcium sulfonate?
Polyurea greases (2014)
Calcium sulphonate thickeners
Calcium sulphonate water resistant greases
Diurea chemical structure
Polymers in greases - Go to page 20
Dow Corning Molykote silicone-based high-temperature greases
Dow Corning - Molykote G-900X Series high-temperature (220 °C) greases (2017)
Axel Christiernsson - The ability of a greases to withstand, reject or absorb water
Axel Christiernsson - The effect of water ingress on environmentally adapted greases (2017)
Understanding grease compatibility
Grease compatibility
Elba - Grease compatibility
Elba - Grease compatibility
LE - Grease compatibility
Mobil - Grease compatibility
Grease compatibility and innovations (2016 forum)
Practical experience with grease incompatibility

When converting from one grease to another, double check to make sure that your soap bases and oils are compatible. The short and simple way to do this is to have your supplier or an independent test lab perform a worked penetration test on a mixture of the greases. Mixing greases can change performance. More often, mixing leads to loss of consistency, but for some mixtures, hardening may occur. Mixing of greases can also result in lowering of dropping points and changes in oil bleed rate. Individual grease lubricants most often perform better than the grease mixtures.

7.4 Grease lubricated rolling element bearings

Developing an effective motor bearing re-greasing strategy
Timken - Applying lubricants correctly
The basics of an electric motor re-grease program
Lubrication of rolling bearings - Technical solutions for critical running conditions
Diagram: Re-lubrication intervals
Electric motor bearing greasing basics
Mobil - Guide to electric motor bearing lubrication
Initial fill grease quantity
SKF - Replenishment
SKF - Quick tool for re-lubrication calculation
SKF - Lubricator calculation program
Other SKF calculators
LubeCoach calculators
Prolonged bearing life through effective grease lubrication
Re-greasing: How grease kills
SDT Ultrasound Solutions - LUBExpert
SDT Ultrasound Solutions - LUBExpert brochure
Rexnord - Greasing (contrary guidance)
Determining lifespan for lubed for life bearings
Grease-lubricated electric motors with grease relief valves (2017)
Stop pumping oil into bearing grease
Ultrasound Solutions - LUBExpert re-lubrication tool (2017)
Ultrasonic energy measurement to improve effective lubrication practice (2012)
Timken - FAQ
tribonet - What contributes to thicker grease films?
Rolling element bearings (links)
Rolling element bearing failures (links)
Electric motors: Keep it clean, keep it dry, keep it tight (2017)

Temporary shear thinning at a high shear rate happens in greases but the base oil viscosity may be permanently reduced. This happens under extreme conditions, such as in the case of high pressure, where the viscosity is very high. These conditions occur in the EHL contacts of rolling bearings. That's why viscosity modifiers (VI improvers) should not be used in bearing (and gear) oils.

Outer-ring rotation causes very severe conditions for the grease in the bearing. The grease on the shields or covers is subjected to centrifugal forces exceeding the yield stress, resulting in the grease flowing continuously into the bearing and causing churning, heat development and high temperatures. Moreover, grease on the bearing outer-ring shoulders or seals will show accelerated oil bleeding. In the case of outer-ring rotation, the base oil/grease is easily lost, and good sealing is therefore a prerequisite.

Roller bearings require a softer grease than ball bearings (on a horizontal shaft). Angular contact ball bearings pump grease through the bearing from the small inner ring diameter side ("low side") to the larger inner ring diameter side ("high side"). In order to prevent this, ideally a stiff grease is preferred on the "low side" and a softer grease on the "high side." Vertical shaft applications require a stiffer grease to prevent grease falling into the bearing.

At very low temperatures, the tendency of grease to bleed decreases and the hardness (consistency) of the grease increases. This may ultimately lead to an insufficient supply of lubricant to the contact surfaces of the rolling elements and raceways so the normal lubricating ability of the base oil in the grease can be diminished. It will then be the grease in its totality that will lubricate. This will result in a high torque, which may cause slippage of the rolling elements and therefore wear. This point is called the low temperature limit (LTL).

7.6 Grease-filled gearboxes

How not to lubricate a gearbox
Discussion: Grease for gearbox?
Mobilux EP 023
Using grease for gear lubrication

Grease-lubricated equipment should not be kept idle for long periods. The base oil in the grease could separate out and get drained from the thickener, which does not have any lubrication properties. Stop and think about all of your equipment to evaluate the potential risks of grease separation.

7.8 Grease or oil?

Understanding lubricants Part II
Oil lubrication vs. grease lubrication (video)
Grease vs. oil debate Is it advisable to use grease instead of lubricating oils?

The bleeding rate, which is the bleeding per unit of time, should ideally somehow match the starvation rate. In the beginning of bearing operation, the lubricant film will be relatively thick and no additional feed of base oil is required. A too high bleeding rate will exhaust the grease at an early stage, leading to short grease life. If the bleeding rate is too low, the contacts will starve rapidly, leading to early damage.

8. Bearings (also 8.2)

Add oil circulation for greater reliability The inner life of bearings, Part I: How lubrication really works
The inner life of bearings, Part II - Lubricant selection and application frequencies
Tribological design guide part 1: Bearings
Tips for better process pump lubrication Is your bearing getting fresh grease?
Wikipedia - Plain bearings
A case study: Plain bearing failures
Self-Lubricating bearings (2017)
Bearing materials

Extreme applications - spindle oils, sugar mills, Morgan and Danieli

Castrol spindle oils
Castrol Hyspin Spindle Oil E 5
Mobil Velocite spindle oils
Sugar mill bearings
Castrol - Biodegradable sugar mill lubricant
Shell Morlina S2 BA oils for Morgan and Danieli

Clean, dry oil is essential to maintain healthy equipment life and prevent shut-downs.

8.1 Rolling element bearings

MIT - Rolling bearings
Rexnord - Checklist: specifying bearings for beverage application
FAG - Rolling bearing lubrication
Klüber - Lubrication of rolling bearings (44 pages, 2011)
Klüber - Guide to proper bearing lubrication procedures (12 pages, 2017)
How rolling element bearings work
Bearing clearances and fits
SKF - Articles - Select Mechanical Maintenance (need to register)
Bearings, Belts and Chain - Care and maintenance of rolling element bearings
Bearings, Belts and Chain - Articles
Five ways to prevent bearing failures
Bearing news - Articles
Lubrication of pumps
Tips for better process pump lubrication
Manual or automatic lubrication? How to decide
UE - Subsurface fatigue and bearing life (2013)
Gearbox bearing service life
Tribological bearing testing
Can WD40 be used as a bearing lubricant?
Using oil mist to lubricate process pumps at high temperatures
Graphene-based nano-lubricants
Nano-technology improves bearing performance
NSK develops automobile transmission bearing with solid lubricant film
A 'solid' concept for bearing lubrication

When a properly packed bearing starts up, there will be an initial rise in the temperature while the grease disperses throughout the bearing and the housing before falling off to a steady operating temperature. If the temperature does not drop, then there is too much grease in the bearing or there is a problem with the bearing fit.

Rolling element bearing failures

(Beyond the scope of the book)
How to determine bearing system life
Lubricant failure is bearing failure
UE - The 50 failure modes of electric motors (2014)
Determining the cause of bearing failures
Common causes of bearing failure 1
Common causes of bearing failure 2
Common causes of bearing failure 3
Hansford Sensors - Identifying bearing failure at an early stage (Accelerometer, 2018)
UE - How subsurface fatigue leads to bearing failure (2013)
Electrical fluting: a current passes through the bearing
Shaft currents can have a destructive effect on electric motor bearings
Warning signs of a bearing failure
Bearing failures
How contaminants influence bearing life
Macpherson curve graph: Effect of oil cleanliness
ISO cleanlines versus time to failure
Deleterious particles in lubricating greases, Part I
Deleterious particles in lubricating greases, Part II
Deleterious particles in lubricating greases, Part III
Oil cleanliness (links)
Water contamination (links)

The top 10 causes of bearing failures (By Ken Bannister):

1. Lack of lubrication training
2. Lack of lubrication-application engineering
3. Poor housekeeping (lack of order and cleanliness)
4. Over-lubrication of bearings
5. Under-lubrication of bearings
6. Use of dirty or contaminated new lubricants
7. Infrequent oil/filter changes
8. Bearing lubricant contaminated with an incompatible lubricant
9. Bearing lubricated with the incorrect lubricant
10. Bearing mounted out of square or misaligned when set up
Note that nine out of 10 items on this list are due directly or indirectly to ineffective lubrication practices.

8.4 Steam turbines, varnish

Book: Turbine lubrication in the 21st century
Chapter in a book: Turbine lubricating oils and fluids
Chapter in a book: Turbine oils
Steam turbine oils: what you should know (2007)
Rob Profilet - A key factor in system reliability
Rob Profilet - Turbine oils, a key factor in system reliability (webinar)
LE - Steam turbine oil challenges
How to select and service turbine oils
Steam turbine lubricating oil characteristics
Fluitec - Turbine oil selection
Fluitec - Look beyond the specification sheet when selecting turbine oils
Performance evaluation of turbine oils
Fluitec - Triple your oil life through anti-oxidant replenishment
Mobil - Turbine Oil Condition Monitoring
Optimizing turbine performance and longevity through a proactive maintenance approach
TESTOIL - Turbine oil analysis (some comments confusing = ignore them!)
Lubricant analysis in steam turbines
The surface tension test - is it worth resurrecting?
Electrostatic discharges in lubricants
Dangers of electrostatic discharge in engine oils
Electrical conductivity of oil
Identifying turbine oil cleanliness levels
Oil conditioner reduces bearing wear, downtime
Oil cleanliness (links)
Room for improvement (2011)
Varnish basics
Will varnish vanish? (2018)
Oil Filtration Systems - Varnish contamination in hydraulic and lube oil systems
Fixing varnish (2008 discussion)
10 things you should know about varnish
Measuring and treating varnish formation in turbine oils
C.C.Jensen - Removing varnish from Group II turbine oil having ashless additives
University of California / Chevron - Varnish removal using chemical flushes (2018)
What is varnish? Function of antioxidants
Mechanisms of varnish formation and implications for the use of varnish-removal technology (2017)
Best strategies for managing varnish
Vanishing varnish
Catching varnish before it costs you (2006)
Reducing the varnish tendency of a Group II base oil by increasing the solvency
The new ASTM Standard for varnish potential
MPC Lubricant varnish potential test (video)
When to test varnish potential (short)
Fluitec - Membrane Patch Colorimetry (MPC) test ASTM D7843
EPT - MPC varnish potential testing ASTM D7843 (2016)
How to detect varnish in turbine oils
Effective varnish removal from turbine lubrication systems
Balanced charge agglomeration for turbine oil purification
C.C.Jensen - Filtering excessive varnish formations
ISOPur Fluid Technologies, Inc. - 55000 varnish-free hours using BCA oil purification
ISOPur Fluid Technologies, Inc. - 55000 varnish-free hours using BCA oil purification GE 7FA turbines
Soluble Varnish Removal (SVR) - Lube oil varnish removal success
Varnish and Soluble Varnish Removal (SVR)
C.C.Jensen - Varnish removal
C.C.Jensen Varnish removal unit
Wear Check - Measuring and treating varnish formation in turbine oils
TESTOIL - Varnish potential analysis
TESTOIL - Varnish potential analysis report
Kleentek electrostatic oil cleaners
OILKLEEN electrostatic filtration system (YouTube videos)
Clean solution: Varnish removal by a new additive in fluid
Hydraulic oil additive package designed to combat varnish deposits

Varnish is a thin, hard, lustrous, oil-insoluble deposit, composed primarily of organic residue.

9.1 Air compressors, coalescer filters

Wikipedia - Gas compressor
Different types of compressors
How reciprocating compressor works (video)
Wikipedia - Reciprocating compressor
Reciprocating compressor
Wikipedia - Rotary screw compressor
Mobil - Oil flooded rotary air compressor
Evaluate a rotary screw lubricant before you buy
Compressed air tutorial
Compressors (animated)
Compressor lubricants
Compressor oils by manufacturer
Mobil Rarus 400
Castrol compressor lubricants
TOTAL compressor lubricants
Mobil Rarus 800 diester
Mobil SHC Rarus Series
Mobil SHC Rarus 46
Wikipedia - Buna-N material for seals
Discussion: PAG vs. ester in compressors
Coalescing filter
Compressed air filters
Coalescing filter
Advanced analysis of reciprocating engines, compressors and gas pipelines
Compressed air for food plants (pdf)
Wikipedia - Diving air compressor
MACO (Gardner Denver) - Brochures: Breathing air solutions

While many compressors will run well at an ISO code of 17/14/11, if the compressor is highly critical, the target may need to be reduced to 16/12/10.

9.2 Vacuum pumps

Wikipedia - Vacuum pump
Vacuum pumps (dictionary entries)

9.3 Compressors for other gases

Choosing a safe lubricant when working with oxygen or reactive gases
Halocarbon - Source for fluorochemicals and inert lubricants

9.4 Refrigeration compressors

Refrigeration compressor lubrication
Oil in refrigeration systems
Refrigerant reference guide
Refrigeration oil
Compressor protection starts with a knowledge of refrigerant-oil basics
Naturals get new push at Atmosphere America
Wikipedia - Vapour-compression refrigeration
Wikipedia - List_of_refrigerants
Wikipedia - Chlorofluorocarbon
Refrigeration lubricants: Transitioning to new refrigerants
Oil management
Wikipedia - Polyol ester
Synthetic refrigeration oils - humidity related difficulties and solutions
Field and laboratory evaluations of lubricants for CO2 refrigeration
DuPont - Lubricant selection guide
Fuchs Refrigeration oils
Mobil - Refrigeration lubricant selection for industrial systems
Mobil-branded refrigeration lubricant selection guide for industrial systems
Mobil EAL Arctic series
Mobil EAL Arctic series (Product data sheet)
Mobil SHC™ Gargoyle 80 POE for carbon dioxide refrigeration compressors
Shell Refrigeration Oil
Shell Refrigeration Oil S4 FR-V
TOTAL refrigeration oils
Vescolub refrigeration oils - See oil selection
Bitzer B5.2 lubricant for ammonia systems (2011)
Bitzer - Retrofitting R22 systems to alternative refrigerants (2011)

The Shell Clavus 68 was a naphthenic oil recommended for all types of refrigeration systems such as ammonia, and CFC and HCFC refrigerants e.g. R-11, R-22, R-500, R-502, R-22, and R-123. The Clavus oils were not recommended for use with HFC refrigerants such as R-134a.

Shell Refrigeration Oil S4 FR-F 68 is a synthetic polyol ester base fluid that is recommended for use with R-134a and other HFC refrigerants and blends. According to the literature, it is not recommended for use with other refrigerants such as R-22.

Shell Refrigeration Oil S4 FR-V 68 is a synthetic refrigeration lubricant based upon alkylated benzenes. It offers a universal solution to the lubrication requirements of most refrigeration compressors and is compatible with all commonly used refrigerants such as R-22 with the exception of HFCs such as R-134a. However, S4 FR-V 68 base stock is not compatible with Clavus 68 and if you are switching you need to thoroughly flush the system including lines and pump to prevent compatibility issues.

10. Hydraulic systems

(Beyond the scope of the book)

Baffles are used to prevent fluid just returned to the tank from passing directly back to the pump inlet. For a number of reasons, a longer transit path is considered beneficial; it encourages better heat conduction from the fluid, better contamination and air separation, and better mixing with the bulk fluid. This is usually accomplished by separating the inlet and outline by as long of a flow path as feasible.

Hydraulics vocabulary - Scroll down
Basics of hydraulics
Fundamentals of hydraulics (video)
Fluid power basics
Wikipedia - Hydraulic pump
Hydraulic pumps
Vane pump failures
Restriction at the pump inlet - discard the suction filter
How hydraulic machines work
How Caterpillar backhoe loaders work
Hydrostatic transmissions
Understanding hydrostatic transmissions
Troubleshooting hydrostatic systems (2016)
Hydraulic accumulators
132 cardinal sins of hydraulics
Top 5 hydraulic mistakes and best solutions
Six costly mistakes most hydraulics users make
Tests to increase the reliability of hydraulic systems
Putting the brake on water hammer in hydraulics
3 ways to detect cavitation wear in hydraulic systems
Cavitation or aeration? How to tell the difference (2017)
Controlling aeration in hydraulic systems
Controlling hydraulic oil temperatures (2016)
Causes of darkening hydraulic fluid
Why hydraulic oil changes colour
Petro Canada - The fight against sludge
11 simple steps for flushing a hydraulic system
Pulsating hot oil flushing technology
Understanding filter debris analysis
Electrostatic discharges in lubricants
ACE - How to avoid hydraulic troubleshooting mistakes
Troubleshooting hydraulic proportional valves (2017)
Three ways to reduce hydraulic shock
Failure mode and effects analysis (FMEA)

Suction line leaks can cause air entrainment and problems such as excessive aeration, air lock, pump cavitation, poor lubrication and premature oil degradation. While a pinhole-sized suction line leak can be hard to find, using a small amount of shaving foam sprayed over the suspected leak area can indicate the source of the problem, as the foam is drawn into the line. This method should not be used for large leaks, and care should be taken not to use too much soap, since this can cause contamination of the lube, resulting in foaming and aeration problems and poor demulsibility.

10. Hydraulic fluids

Wikipedia - Hydraulic fluid
Evonik - Hydraulic fluids (2017)
Hydraulic fluid selection and maintenance (2015)
Selecting hydraulic fluid
MachineDesign - Hydraulic fluids
MachineDesign - Fluid performance factors
Performance classes for hydraulic oils
Hydraulic fluids
LE - Hydraulic fluid selection and maintenance
Does your hydraulic fluid provide enough protection?
Why hydraulic oil is different
Which hydraulic oil should I use?
Advantages of zinc-free hydraulic oils (US perspective)
Important considerations for choosing hydraulic fluids
Brendan Casey - Choosing the right hydraulic fluid
Brendan Casey: Limits for hydraulic fluids
Understanding hydrolysis and hydrolytic stability
Testing hydraulic fluids
A hydraulic fluid choice - showing the optimum operating range...and references
Peter Mainka's hydraulic views
A hydraulic fluid saves energy
How to improve hydraulic efficiency
Hydraulic oil can make a major difference to power consumption
Bosch Rexroth - Validated hydraulic fluids increase the service life of the hydraulic system (2018)
Bosch Rexroth - Press release (2015)
Bosch Rexroth - Press release (2016 - click to download fluid rating list)
Bosch Rexroth - Data sheet No. 90235: Rating of hydraulic fluids (2015)
Chevron hydraulic fluids
Shell Tellus brochure
Shell Tellus S (original version)
Rhein Chemie - dispersant and emulsifying type (HLPD) additive pack
Afton - HiTEC 521 Anti-wear hydraulic additive package

Use the right hydraulic fluid, keep it clean, and replace it when it does not look good. You can often see and smell the general condition of a lubricating oil.

10.1 Fire-resistant fluids

A page in a book: Fire resistant fluids in turbines
Chapter in a book: Fire resistant fluids in turbines
Fire-resistant fluids (pdf)
Fire-resistant fluids (text)
Rexroth - Axial piston units for use with HF Fluids
Mobil - Fire-resistant fluids, conversion and compatibility
Using water-in-oil emulsions
Advice for using water-in-oil emulsions
Measuring emulsifier performance
Water-glycol fire-resistant hydraulic fluids
Dow's UCON - Water-glycol hydraulic fluids
Fire-resistant HFC hydraulic fluids
Quaker QUINTOLUBRIC fire-resistant fluids
Quaker QUINTOLUBRIC fire-resistant hydraulic fluids (video)
Phosphate esters
Electrohydraulic fluid
Phosphate ester, the true fire-resistant fluid (video)
Seal compatibility - Select Pyrogard
Maintenance of fire-resistant fluid (phosphate ester) 2007
Maintenance of fire-resistant fluid (phosphate ester) 2013
Controlling the acid in phosphate ester-based hydraulic fluid
Heat of combustion, flash point, autoignition temperature of PAG
Effects of water on PAG
FM Global

Factory Mutual, FM Global, is a US-based mutual insurance company which assists businesses worldwide. The company carries out its own scientific research, approves fire protection equipment (FM Approvals) and publishes its own installation regulations (FM Data Sheets - FMDS). FM Global assesses the risks of its policy holders, appoints a project engineer to produce protection system recommendations and, upon completion of the work, the project engineer is brought in to verify that the protection provided complies with his recommendations. FM Data Sheets are recognised standards for fire protection in industry. They are available to consult free of charge and other insurers may use them as their standard.

Given a high enough temperature, all hydraulic fluids can be ignited when coming into contact with an ignition source. The real test of fire resistance is whether a fluid is capable of self-extinguishing. The ability to self-extinguish can make the difference between a momentary flash that causes no harm and a conflagration, which results in injury to personnel and/or loss of equipment. Only phosphate esters offer such fire-resistant characteristics.

Trixylenyl phosphate fluids are used in large steam turbines of nuclear power plants where temperatures reach high enough to ignite mineral oils. These synthetic fluids are extremely difficult to ignite and inherently self-extinguishing. Besides their high oxidative and thermal stability, they can contain water and have good hydrolytic stability.

10.2 Oil cleanliness
Particle counting, cleaning oil, filtration
Oil filters

11. and 13. Lubricant storage and storage life (shelf life)

Y2K Filtration - Lubrication, dispensing, storage and management
Store it safely, handle it right (2017)
SAIT - Lubricants storage: best practice (2016)
Improved oil storage and handling produce cost savings (2015)
Improving storage and handling (2017)
Best practices for lubricant storage and handling
Best practices for lubricant storage and handling
a href="">Noria - Storing oil drums (short video)
Elba - Storing oil drums
Storing oil drums outside
Storing oil drums (short video)
Best practices for lubricant storage and handling (short video)
Options for lubricant storage and handling
Storing grease to avoid bleeding
Advantages of proper lubricant storage
Lube room essentials
How to manage lubricant storage
World class lube room
Bulk lubricant storage and handling
Bulk lubricant storage
Preventing cross-contamination in bulk lube oil storage systems
Modern methods of lubricant storage

Clean Lube Solutions - Storage equipment
When to use hard-pipe lubricant dispensing
Lubricant storage life
Mobil - Shelf life
Chevron Marine - Shelf life

Avoid the use of galvanized steel storage and dispensing containers. The zinc in the galvanizing can act as a catalyst to promote lubricant oxidation and premature depletion of critical additives. There are many other types of more chemically stable platings for metal containers. Stainless steel or plastics are also suitable alternatives.

12. Transformer oils

Wikipedia - Transformer oil
The transformer and its oil
Transformer selection and maintenance
Specifications of a transformer oil
Intertek - Transformer oil tests
SGS - Transformer oil analysis
Testing transformer oils (2013)
GlobeCore - Oil regeneration extends transformer life by 20 years
Nynas transformer oils
Shell Diala GTF transformer oil
Vegetable oil as insulating fluid for transformers
Natural ester oil application in liquid filled transformers (2.5 Mb)

The oil in a transformer serves as an insulating medium which is used for cooling, protecting the paper and for analysis. Regular oil analysis is considered one of the most critical activities that will assist in monitoring the condition of the transformer and facilitate predictive servicing. The oil analysis regime should include dielectric strength, water content (Karl Fischer), acidity, interfacial tension and dissolved gas analysis (DGA) that provides a clear indication of internal failure conditions. The oil should be analysed to determine if polychlorinated biphenyls (PCBs) are present. Furanic analysis should also be done as this will determine the cellulous breakdown products in the oil and give an indication of the life expectancy of the insulation in the transformer. High moisture will result in dielectric breakdown.

14. Machine tools

Lathe lubrication
Way lubricants
Elco slideway lubricant additive
Scroll down to BASIC LUBRICATION articles
Test kit for metal working and steel plant fluids

15. Cutting fluids, metal cutting, grinding

Metal working fluids
Tutorial on cutting fluids
Cutting fluids
Wikipedia - Cutting fluid
Noria - Choosing metalworking fluids (short)
Properties a cutting fluid should have
Cutting fluids (coolants)
TLT - Formulating water-based metalworking fluids (2017)
How metal working fluids can boost machine shop productivity
Optimising metalworking fluids - good practice guide
Minding the metalworking fluids
Metalworking fluid troubleshooting guide
Guidelines for selecting additives in metalworking fluids
Amines 101 for metalworking fluids
Chlorinated paraffins
ILMA clarifies confusion over anticipated EPA action on chlorinated paraffins
Metal working fluid microbiology (2018)
Metalworking fluid discovery of the century?
Castrol cutting fluids
Fuchs soluble cutting fluids
Minimum quantity lubrication
Minimum quantity lubrication reduces total costs of operation (2017)
Selection and use of grinding wheels (1965)

Lead enhances metal machinability. Traces of lead are added to steel, aluminium and copper alloys for rapid, accurate and efficient machining with currently available tools and metalworking fluids. The lead reduces friction between machine tools and parts, allowing faster production of parts and lower energy consumption.

16. Rust preventives

Protect equipment in short-term storage, stand-by or decommissioned
Preserve equipment by oil mist lubrication
Wikipedia - Rust
Keep rust and corrosion from crippling your productivity
Rust protection oils


Answers to REVISION 3 (link)


Hint No. 2 (link)
Hint No. 3 (link)
CHALLENGE solution (pdf)


Answers (link)

The following sections, except 'Oil cleanliness', are not covered in the book

Suppliers' information, approved and recommended lubricants (no endorsements, for information only)

Product equivalents
LubriTec - Synthetic SAE 50 lubricant cross reference
B’laster Corporation - PB Penetrating Grease
CASE - Commercial / Farm / Earth-moving lubricant recommendations
Castrol oil chooser
Castrol unveils VW's first 0W-20 engine oil (see also VW below)
Caterpillar lubricants (July 2014)
Caterpillar commercial diesel engine fluids (September 2014)
Cepsa lubricants
Cummins approved product lists
Cummins issues new CES 20086 oils list
Cummins OilGuard extends oil drain interval for X15 Series heavy-duty engines
Cummins recommends fuel additives
Dow Corning - Molykote G-900X Series high-temperature (220 °C) greases (2017)
ELF announces 0w-20 oil for Volkswagen (VW 508.00 / 509.00) and Porsche (C20) (2017)
Eni product brochure download (interesting)
Evonik additives (VII, PPD)
FL Smidth - Key to lubricants
Fuchs’ Titan Cargo MAXX SAE 5W-30 meets Scania’s LDF-4 requirements
Functional products additives
dexos engine oils (9' video)
General Motors - approved dexos1 and dexos2 engine oils
dexos1 Gen 2 taking off (October 2017)
GM dexos1 Gen 2 licensed oils list now contains 168 oils (July 2017)
General Motors dexos1 April 2017 update
General Motors dexos2 licenses (2017)
General Motors - The new GM dexos2: It’s complicated (2016)
Generation Systems Inc - LUBE-IT software (2018)
Gill - Oil condition sensors (2018)
Harvard - Filters, carts (2018)
IFH Group - Carts (2018)
Klüber articles, e.g. Bearing lubricating procedures
Lubrizol additives
Mack Trucks - Approved oils
Mack Trucks announces extended oil drain interval for genuine oil
Mobil greases
Mobil product selector
Mobil - Optimum performance with energy efficiency built in
MOLYKOTE - Machinery problems solved by selecting products
NATO's lubricant specifications
Porsche launches motor oil for classic cars with air-cooled engines
Shell products
Shell lubricants
Shell Rotella product selector
Shell recommendations
Shell unveils CK-4, FA-4 strategy
Spectro Scientific - Instruments (2018)
Swift Filters Inc (2018)
Todd Technologies Inc - Breathers (2018)
TOTAL lubricants
TOTAL industrial lubricants
TOTAL industrial greases (USA)
TOTAL industrial greases (UK)
TOTAL LHM PLUS hydraulic fluid for CITROEN
Valvoline - Synthetic petrol engine oil to combat carbon build-up (2018)
VW oils explained
Wolf releases OFFICIALTECH 0W20 LL FE motor oil for new VW engines

Lubricant monitoring, sampling and analysis

Monitoring equipment without special instruments and without laboratory samples

Oil analysis is not simply about a periodic sample pulled from a machine and sent to a laboratory. A lot of organisations today are empowering their maintenance staff and operators to do a certain amount of quick, on-site inspections and field tests. The concept of a frequent inspection, what is called a daily one-minute inspection, can far exceed the benefits of monthly or bimonthly oil sampling where very sophisticated laboratory testing is done.

Many equipment inspections are visual, and checking oil levels is the most common visual monitoring activity. Numerous potential machine failures are prevented by an attentive individual who notices a low oil level. Other valuable functions can also be performed as part of the visual inspection. Lubricant issues such as oil contaminated with water or other materials, badly degraded or oxidized oil, and excessive foaming, as well as other machine conditions including excessive vibration, loose belts, loose drive chains and loose or missing fasteners are all examples of what should be routinely documented and scheduled procedures.

In machinery condition monitoring, a decision on the condition of a machine is dependent on the nature of its signals. For example, if the machine produces excessive noise and vibration, one gets a clue that something is not normal with the machine. These signals are usually time varying and need to be understood because they carry the information from the machine to the decision system, which can be a developed software or a person.

Temperature is a very important parameter to be monitored, in particular for bearings and shaft couplings. Many instruments are widely used for temperature measurements. At high temperatures, when mounting or access to machines is a problem, non-contact instruments like pyrometers and thermal imaging cameras are appropriate.

While pulling a sample from a reservoir, an exceptional amount of air was found in the hydraulic fluid. The suction-side components were sprayed with mineral oil to locate where air was being ingested. The pump became quieter after the input shaft seal was sprayed. The sprayed oil was seen being drawn into the pump. A check of the pump revealed a worn bearing and shaft seal, which were attributed to oil contamination. The pump was replaced, and the source of contamination entry was located. The bottom line is to listen when your oil talks to you.
(Mike Deal, Alcan Aluminum)

Inspection 2.0 for early fault detection (2016)
Noria - Condition monitoring with Inspection 2.0 (webinar)
The daily one-minute inspection
Utilizing your senses as Condition Monitoring tools
Checking the colour of the oil (short video)
What's that smell? Using odor as an oil analysis tool
How to give your machine a physical
Regular inspection of critical lubrication parameters
How to troubleshoot anything
FluidRX One Drop Fluid Analysis Kit (patch)
Esco - Magnetic oil monitors
Deutz: Oil performance check (patch)

Oil and grease sampling

SUMMARY: Effective oil sampling
(Trico Corporation)

The sampling technique that gives the most representative sample is one in which the sample is taken from a pipe carrying oil scavenged from the wearing parts and before filtering. Clearly, it is necessary for the machine to be operational to do this. Care must be taken that the sample is representative of the complete system, i.e., that the scavenged oil has passed through all the wearing parts.

To achieve the most representative and 'trendable' information from oil sampling, follow these basic tips:

1. Samples should be collected when machines are running at normal operating temperatures, loads, pressures and speeds. This will ensure that insoluble and semi-soluble (dirt, water, and other debris) material is suspended evenly throughout the system.

2. Sample upstream of filters and downstream of machine components such as bearings and gears to obtain the best data. Sampling downstream from the filters should be performed if you wish to determine the effectiveness of your filtration system.

3. Document oil sampling procedures for each system - tools needed, line flushing requirements, sampling locations, sampling methods, and safety requirements are among some of the items to include in the written procedures. This ensures that each sample is taken in the same manner and from the same point. Procedures that are documented also help new employees quickly learn the process.

4. Properly flush sampling valves, devices, and hardware thoroughly prior to taking oil samples. To avoid cross-contamination, use a new sampling tube for each sample taken.

5. Make sure that oil samples are taken at the proper frequency and that the frequency is sufficient to identify problems. Sampling frequencies should be set specifically for a particular machine. Every machine is unique in its intended performance, condition, locality, operating environment, and maintenance schedule.

6. Forward samples immediately to the lab after sampling. Ideally, oil should be analysed within 48 hours of being sampled.
TESTOIL - How to consistently collect a representative sample (webinar)
Oil Sampling Do's and Don'ts
Advice for quality oil sampling (short video)
Sampling procedures
Proper bottle sampling technique (short video)
Sampling instructions
Good oil analysis starts with good sampling practices
Noria - Sampling location - wet sump (video)
Sampling points
World-Class Oil Sampling - It is Possible
Noria webinar: Best practices for oil sampling
Oil sample extraction tools
Sampling is key to oil analysis accuracy
Tips for flushing your sampling equipment (short video)
Lubricant sampling design and implementation
Particle settling and oil sample agitation (2015)
Test yourself question
Hydrodynamics and oil sampling
TESTOIL - The importance of oil sampling on a-regular basis (2018)
Tools for effective grease sampling
Grease sampling methods outlined in ASTM D7718
Quick and easy test for grease conditions
How to obtain grease sample from pillow block bearing
Why you should inspect bearing grease discharge

When possible, don't take oil samples from cold systems. Samples that are consistently collected from cold systems will have altered concentrations of wear metals, contaminants and other insoluble suspensions. When at rest, anything heavier than the oil will begin to settle. It takes only two minutes for a 20-micron particle of Babbitt bearing metal to settle 1/2 inch in an ISO 22 bearing oil. If unavoidable, cold systems should be labelled as such.

With the proliferation of digital cameras, why not take a photograph of the oil sample (requires the use of a transparent sample bottle) and store the image in a trending software for comparative purposes. Record a new oil sample and use this as a baseline. Set the bottle against a white background such as a sheet of paper to maintain a consistent color comparison. You can also use the camera in other ways such as to record images of the machine and sampling point as a means of identifying it in the software or to record abnormalities.

Sampling frequencies

Establishing effective sampling frequencies (Revised in the next link)
Establishing oil analysis frequency
The importance of machine criticality
Criticality analysis for machinery lubrication (2013)

The appropriate sampling frequency is determined by the nature of the machine, its use and how important early warning is to the user. Experience has shown that in many failures abnormal wear particles were present in the lubricant, indicating that the machine was defective from the start. The reasons for this are easy to see. Many failures are the result of improper assembly, a defective part or poor design. Such difficulties result in abnormal wear debris from the beginning.

Designing oil analysis programme, condition monitoring, standard test methods

Managing effective fluid analysis: 10 steps to realize your return on investment (2018)
4 ways to improve your oil analysis program
How to avoid machine failures with routine oil analysis
Implementing world-class oil analysis (short video)
Why oil analysis programs fail (short video)
10 steps to create a world-class oil analysis programme
5 keys to a successful oil analysis program
Best practices for using oil analysis in lubrication management (2017)
Noria - How to get maximum value from your oil analysis program (webinar, available until 27 June 2018)
The benefits of route-based oil analysis
Selecting the right oil analysis lab (2016)
Oil analysis and its role in equipment reliability (2017)
FTIR oil analysis (2015)
Understanding the 'Rights' of oil analysis
Tracking the life cycle of your lubricants
A practical approach for evaluating oil analysis results with limit values
How to select machines for oil analysis (2015)
How to select the right oil analysis tests
Engine oil analysis (2016)
Bureau Veritas - Case study: Gear oil laboratory tests, water contamination (2017)
Effective use of the patch test for simple on-site oil analysis
Is oil analysis a waste of time?
Predicting machine failure with oil analysis (short video)
The 'rights' of oil analysis
Six steps for more effective oil analysis
5 steps to best in class oil analysis
Oil analysis optimization
How to develop an effective oil analysis strategy
Setting up oil analysis programme
Do oil and coolant analysis together

A major mobile equipment manufacturer estimated that an average of 53 percent of all engine failures are a direct result of problems with the cooling system. Periodic coolant analysis, including glycol content, pH, conductivity, inhibitor analysis, visual inspection and resistance to corrosion, may be as valuable as routine oil analysis in preventing failure due to the cooling system.

While oil analysis can't fix a failed machine, it can provide pre-failure alerts, both cautionary and critical. If a root cause is detected, such as the wrong oil, dirty oil or wet oil, these conditions can then be remedied quickly.

Oil condition monitoring keeps equipment healthy (2017)
Choosing and implementing a successful condition monitoring programme (video 45 minutes)
Unified condition monitoring approach
PALL- Crixus fluid condition monitoring platform - moving from reactive to predictive fluid maintenance (2017)
Noria- Lubrication best practices at Sinclair (2017)
UE- Remote monitoring platform to revamp PdM process (2017)
Improving maintenance strategy with online condition monitoring
Common mistakes in CM programmes

According to the Electric Power Research Institute (EPRI), online monitoring is the implementation of applications for monitoring, maintaining, and optimizing assets from a centralized location. Such monitoring becomes necessary in today's fast-evolving global economy for companies that rely on assets as they face increasing reliability concerns. Unexpected downtime and maintenance can lead to significant cost and safety repercussions that can easily affect a company's bottom line.

LE - Industrial application condition monitoring by oil analysis
LE - We have not replaced our gear oil in 8 years
Polaris - Make oil analysis an integral part of maintenance programme
Analysts, Inc. - Proper testing for maximum value and equipment condition information
Selecting machines for oil analysis
Selecting machines for oil analysis (discussion)
Improve gearbox reliability with oil analysis and contamination control
Laboratory analysis of a used-oil sample
Grant Dawson - Choosing the right diesel engine test package
Spectro - Oil analysis handbook 2014-08 (pdf)
Spectro - Clarify the mystery of in service oil analysis techniques
Test explanations
Oil analysis tests and their significance
Oil analysis test method standards
TESTOIL - Oil analysis lab test methods
Lubetrend - Learn oil analysis - How to read an oil sample report (video, 2018)
Three common contaminants and the oil analysis tests that can detect them
H Adeni - Testing lubricants and its significance
Koehlerinstrument - Test methods for lubricating oils
Laboratory test method codes and sample sizes
Savant - Laboratory services
Sample report with explanations
TESTOIL - Sample reports
Key oil analysis metrics

Root causes of failures, advanced test methods

Root cause analysis techniques for the lubrication professional (2002)
Root cause analysis for lubrication failures (2006)
Medical Device Academy - Root cause articles
Root cause analysis, four different investigation tools
Root cause analysis slides
The power of root cause pre-failure analysis (2016)
Root cause analysis training (2017)
Root cause analysis, calculators, tools and assessments (2017)
Proven methods for determining the cause of machine failures (2016)
How to diagnose machine failures (2002)
Reliability-centered maintenance and root cause analysis(2008)
UE - The 100 failure modes of lubrication and lubrication programs
Acculube - There are 4 main reasons lubes fail (2017)
Root cause analysis
Quant - Improving equipment reliability through the implementation of Root Cause Analysis (RCA)
Pinnacle - Root cause analysis
Finding the root causes of oil degradation
Determining the cause of oil degradation
How engines consume oil ... and oil analysis results (2016)
Some interesting blogs in English - Scroll and click 'Older Posts' to 19 May 2013: Maintenance isn't just repair
TESTOIL - Filter debris analysis
TESTOIL - Filter debris analysis report
New advances in wear debris analysis
Microscope (short video)
V4L - CADET Particle analysis demo (short video)
Dangers of small particles and test methods discussed(2018)
Evan Zabawski - Comments on specroscopy
Wear limits vs. trends
Evaluating the source of Silicon in oil
Sources of Silicon in oil
Sodium in oil
Root causes of Sodium and Potassium in engine oil
The effects of Glycol contamination in engine oils
Water or antifreeze (glycol) contamination (2017)
Identifying root causes of machinery damage with condition monitoring
Hy-Pro - Fluid Analysis Reference Guide
Fluitec - Membrane Patch Colorimetry (MPC) test ASTM D7843
EPT - MPC varnish potential testing ASTM D7843 (2016)
EPT - MPC varnish potential testing ASTM D7843 (2:30 video, 2013)
How light affects oil analysis results for varnish potential (2016)
How to detect varnish in turbine oils
Oelcheck - Warning values for contaminants, additives and wear
Water and oxidation sensor
TESTOIL - Materials identification analysis
UE - Condition-based approach to lubrication
UE - 3 ways to incorporate ultrasound in lubrication testing
SDT - Ultrasound detector
Monitoring large particles in gear oils
LaserNet Fines (LNF) instrument counts and classifies all particles
Ferrography PQ Index
The value of analytical ferrography as a critical exploratory test
Vibration and oil analysis techniques reveal root cause and severity
Microdieseling and its effects on oil

According to Caterpillar, catching a problem before failure occurs results in repair costs that are 5 to 25 percent of the engine's value. Catching a problem after failure occurs leads to repairs that are more than 65 percent of the engine's value.

Today, portable analysers are able to measure many relevant oil parameters at the site with no need to send samples to a laboratory. They can determine oxidation, viscosity, TBN, TAN, water contamination, additive depletion and more.

Analysis interpretation, grease analysis

How to interpret oil analysis reports (2016)
Evan Zabawski - Oil change as a corrective measure?
Lubetrend - Learn oil analysis - How to read an oil sample report (video, 2018)
The wrath of unscheduled downtime: Why oil analysis is a wise and effective defense
Making sense of oil analysis results
TESTOIL - Materials identification analysis report
Oil Analysis: Five Things You Didn't Know
Top 10 oil analysis misperceptions (You can also page through the magazine)
Systematic Oil Analysis Interpretation
Engine oil analysis
Establishing elemental limit values for motor oils
Grant Dawson - Understanding basic oil analysis (video)
Grant Dawson - Oil Analysis: Sources Of Atomic Elements
Grant Dawson - Understanding diesel oil analysis reports
Grant Dawson - Spectrochemical metal limits
Understanding automatic transmission oil sample report
Spectro - Fuel dilution testing in the field
Influence of engine oils dilution by fuels on their viscosity, flash point and fire point
Oil filter analysis uncovers hidden problems
Filter element examination
Grease analysis methods
Grease analysis
Best methods for analysing grease
Grease analysis: Early warning system for failures and proactive maintenance tool

Oil analysis reports frequently lack important test information relating to the machine application and the type of oil, which is essential for proper interpretation. Other common challenges include:
* The same test package is used for different types of machines.
* There is no reason to perform oil analysis if the data obtained is not properly understood. With so much information packed into a few pages, reading lab reports can be overwhelming to the untrained eye. Unfortunately, a majority of plant personnel who receive these reports do not understand the basics of how to interpret them.
* The laboratory analyst has no knowledge of the basics of machinery lubrication and tribology.
* The oil analysis report is received several months after oil sampling.
* The lab does not follow strict procedures as per ASTM/ISO standards.
* There is no quality assurance for meeting the required standards.
* The report contains insufficient information to make any decisions.
* No interpretation or recommendation by the oil analysis lab is included in the results.
* Cross-contamination between various oil samples leads to meaningless results.

10.2 Oil cleanliness

Des-Case - Cost saving calculator
FlowEzy - Dirt affects hydraulic performance (2 pages)
Oil target cleanliness calculator (2013)
Harvard - Cleanliness/lubrication
Bosch Rexroth - Hydraulic fluid cleanliness, 5 tips (2013)
Reducing the effects of hydraulic fluids contamination
Des-Case - Fundamentals of lubricant contamination control (2016)
Contamination control is critical
UE - Controlling contamination to control costs
...don't forget contamination
Sources of contaminants
Contamination control is everyone's responsibility (video)
UE - Controlling contamination to control costs
The causes and effects of hydraulic oil contamination (video)
How silt lock can destroy hydraulic valves (2012)
How to mitigate contaminant ingression in hydraulic systems (2017)
How clean is your hydraulic fluid?
Y2K - New oil is dirty
Cleanliness extends lube, equipment life
Effects of contamination on the pump life (video)
How particle ingression impacts equipment reliability
Spectro - In-service oil and fuel analysis
Spectro - ICP-OES technology
Monitoring large particles in gear oils
Solid particles
Characterization of particles from in-service lubricants (ASTM)
Dirt is harder than metals in machines
Improve oil cleanliness (short video)
Minimizing the impact of built-in contamination in hydraulic systems
5 tips for setting target cleanliness levels
Bosch Rexroth - Importance of hydraulic oil cleanliness and tips to protect your systems (video)
Chevron ISOCLEAN certified lubricants
Causes and hazards of silt lock
Electrostatic cleaning: Valve stiction problem cured by soft particle removal
Clean solution: Varnish removal by a new additive in fluid
Hydraulic oil additive package designed to combat varnish deposits
Steam turbines, varnish (links)
How to interpret oil analysis data
MP FILTRI - Fluid condition handbook (1.2 Mb)
TESTOIL - Hydraulic oil analysis report
Advice for flushing sumps
Some interesting blogs in English - Scroll and click 'Older Posts' to 3 June 2013: Flushing
SWEPCO 728 In-service system cleaner
Gearbox contamination control - Breathers
How to improve desiccant breather life (short video)
Filler-breather adapter simplifies hookups (2017)
Des-Case - Connected breathers (2018)

When installing fine-filtration (3 to 10 micron) reservoir breathers, make sure the breather has an internal differential pressure gauge to alert you when the filter is dirty. If your breathers do not have this built in, add pressure and vacuum gauges to the reservoir head space. Then add inspection of these gauges to your pre-PM checks while the machine is in normal operation.

Translucent new oil is visually assumed to be clean but it often contains more contamination than the existing oil being replaced.

Particle counting, purifying oil, preventing contamination

SAIT - Particulate detection in lubricating oil (2009)
Whyps - Cleanliness monitoring of hydraulic systems
Parker - Guide to contamination standards
Spectro - Particle measurement techniques
How to get the most from tour particle counter
Particle counting - oil analysis 101
Beckman Coulter - Importance of particle counters (2017)
Particles: friend or foe? Understanding the value of particles in oil analysis
Hydraulic oil contamination (NAS, ISO)
Oil cleanliness codes
ISO 4406 Cleanliness Code
How important is the ISO Cleanliness Code in oil analysis?
ISO 4406: What do those numbers mean in the ISO Cleanliness Codes?
ISO Cleanliness Codes (video)
Des-Case - ISO Cleanliness
Elevated particle count - what now?
Value of particle counting in oil analysis
Particle counters
A much closer look at particle contamination
MP Filtri - Continuous contamination monitoring
Advantages of having an on-site particle counters (short video)
Parker - Oil purifier
Contamination control strategies for turbomachinery (2016)
Synthetics, contamination control and oil analysis team up
When fluid that is cleaner than ISO 14/12/9 is required...
Valve stiction problem cured by soft particle removal (electrostatic liquid cleaner)
Des-Case - Desiccant breathers

Be sure to monitor your filter change interval. Premature plugging is usually a sign of a problem that merits further investigation. This may be caused by airborne dust from nearby construction or a prolonged dry spell raising atmospheric dust levels. Whatever the source of dirt, the root cause should be investigated, and the seals or breathers may need to be serviced or upgraded. In certain cases, the problem may be associated with a change in the performance of the filter from your supplier. Extremely long filter life is as much of a concern as too short of a life.

Have you seen a spike in particle counts for a stable circulating oil system where no oil has been added or lost? Check to see if the oil filter was changed just prior to the sample date. It's not uncommon for a spike in particle counts to occur after changing filters due to the system "disturbance." Therefore, don't be too zealous in changing filter elements purely on a calendar basis. Take advantage of their operating life and only change them when they have reached load capacity or been in the system for the recommended service life.

Filtration, filters

When should oil be filtered?
Taher Salah et al., Hydraulics & Pneumatics - Integrated monitoring and filtration in a steel mill (2018)
Des-Case - Filter new oil
TESTOIL - Fluid filtration and the importance of cleanliness (webinar)
Keeping fluid clean in the reservoir (2017)
C.C.Jensen - Off-line fine filter
Hi-Pro - Benefits of offline filtration (2018)
C.C.Jensen - Offline filters for gearboxes
C.C.Jensen case study: Conveyor belts gear box
Harvard - Why supplemental filters?
RPS - Filter carts
Macpherson curve graph
Macpherson curve: clean oil = 70% gearbox life extension
C.C.Jensen - How to use offline filters to rescue dirty gearboxes
Selecting the right oil filter
Understanding filter efficiency and Beta Ratios
Understanding oil filter ratings
C.C.Jensen - Oil filtration
C.C.Jensen - Tools to verify oil filtration efficiencies
How to evaluate oil filters (video)
Oil filters (video)
MP Filtri - Filters (just 2 pages, 2018)
Changes in filtration and contamination - switching directions for the filtration industry
Parker Racor - By-pass oil filtration of engine oil
By-pass oil filtration
How to select the right filtration skid for offline kidney-loop oil filtration (2018)
High viscosity gear oil filtering (short video)
Reducing wear particle generation (filtering and using PAG)
12 guidelines for using oil filters
Hi-Pro - Oil filter elements and media types (2018)
Choosing the oil filter location (2017)
Fundamentals of filters - Select page 18
Matching oil filtration to machine requirements
C.C.Jensen - Oil filters (video)
Hy-Pro - Dynamic Filter Efficiency testing method (2016)
Hy-Pro - Problems with C.C.Jensen cellulose media filters
High viscosity gear oil filtering
PALL - Oil filters and purifiers
Y2K - Removing moisture and particulate contamination
Y2K - All filters are not created equal
Harvard - Oil filter carts (2018)
Additives not removed by filters (2013)

Maintenance tip: Equipment optimisation through modification

More than 75% of all problems in fluid systems can be traced back to contaminated oil. Therefore, proper lubrication goes beyond choosing the correct lubricant; it includes keeping the lubricant free of contaminants and monitoring oil cleanliness is the most important factor in preventing system failures.
You might have to modify the equipment so it remains sealed during all phases of normal operation—including routine maintenance, such as level checks and oil changes. This can be achieved by retrofitting the drain and fill/breather ports with modification kits that permit multiple access points to the equipment without opening the sump to the environment. Modifications should be designed in a way to help you:
- Top up oil
- Check oil level
- Take oil samples
- Drain/fill oil
- Kidney loop oil filtering


When replacing top-suspended spin-on or threaded canister-type filters, fill them with fresh oil before installation. This will reduce the amount of time that the engine or machinery undergoes dry start-up by having that extra available amount of oil available. In some cases, it could also prevent filter damage when a gush of high-pressure fluid hits a dry element.

From Brendan Casey

"Brendan, your book 'Insider Secrets to Hydraulics' motivated me to build a small, kidney loop filter cart comprising a 145 micron screen, pump, water absorbing filter and final 3 micron filter (Donaldson P550275, P565062 and P551550 respectively). A second-hand 3 GPM pump and motor drive the system.

The limiting factor is inlet vacuum at the pump which I limit to less than 5 PSI via a pressure relief valve at the pump outlet which relieves back to the intake side of the inlet filter. That routing was chosen to provide rough filtration and more heat exchange surface for the oil being recirculated within the pump.

With cold hydraulic oil this gets me a throughput of around 1 GPM which I run for several hours to get several full passes. All very modest, but a real money saver. The alternative - annual oil changes - would cost around $450 at today's $15/gallon prices. The total cost of my self-made cart was less than that so it paid for itself in the first year. I suppose I should still change the oil every three years or so to maintain the additives and all. Even at that rate the cart will have reduced my oil cost to one third of what it would have been. Rather satisfactory."

Brendan Casey comments: Is this filter cart design technically perfect? Probably not. Is it effective at cleaning and drying the oil? Almost certainly. Sure, this member needs to get a bit more sophisticated and do regular oil analysis - to know for sure when the oil's additives and/or oxidative life have been used up.



High Velocity Oil Flushing is an essential process to ensure optimal reliability of critical components within hydraulic systems and the lube oil systems of rotating equipment.

Factors to consider before an oil flush (short, 2017)
Automatic transmission flushes (video)
Flushing methods (Solving recurring oxidation problems)
11 simple steps for flushing a hydraulic system
Pulsating hot oil flushing technology
Advice for flushing sumps
Some interesting blogs in English - Scroll and click 'Older Posts' to 3 June 2013: Flushing
Tips for flushing your sampling equipment (short video)
Four types of oil flushes
How to verify system cleanliness after an oil flush (2017)
Alternatives to lubricant flushing

Water contamination

Noria: The presence of water in most lubricants (synthetic or mineral) can cause the progression of oxidation to increase tenfold, resulting in premature aging of the oil, especially in the presence of catalytic metals such as copper, lead and tin. In addition, certain types of synthetic oils like phosphate esters and dibasic esters are known to react with water, which leads to the destruction of the base stock and the formation of acids.
It is not just the base oil that can be affected by moisture contamination. Certain additives such as sulfurous anti-wear (AW) and extreme-pressure (EP) additives as well as phenolic antioxidants are readily hydrolyzed by water, causing both additive mortality and the formation of acidic by-products. These acidic by-products can produce corrosive wear, particularly in components containing soft metals like Babbitt, which is used with journal bearings, as well as bronze and brass components. Other additives, including demulsifying agents, dispersants, detergents and rust inhibitors, can be washed away by excessive moisture. This results in sludge and sediment build-up, filter plugging and poor oil/water demulsibility.

In turbine oils, moisture content could reach 180 ppm before the oil turns cloudy. So the easiest way to check for water is visual, done at room temperature. At 250 ppm, the lubricant is still translucent but hazy. At 500 ppm, it is hazy and opaque. At that level, by decreasing water concentration, lubricant's service life extends almost twice for every 120 ppm water eliminated. There is also the crackle test: if no crackling takes place after placing a drop of oil for a few seconds on a small metal pan at 135 °C, no free or emulsified water is present. If some 0,5 mm bubbles are produced aprox. 500-1000 ppm water is present. For moisture content of more than 2000 ppm, bubbles grow to 4 mm. This method does not measure chemically dissolved water. Other methods would be calcium hydride test and capacitance change of the sample or FTIR or Karl Fischer.
Denisa Ivana

Humidity saturation limits of lubricating oils (2012)
Why water and oil don’t mix - and what to do about it (5.5 Mb)
BioKem - Moisture could be your No. 1 lube oil problem
How water causes bearing failure
Oil and water shouldn't mix
LE - Water contamination
Understanding oil's saturation point
Humidity saturation limits of hydraulic and lubrication fluids
Water-related damage to rolling element bearings (video)
Impact of Water on EHL Film Thickness of Lubricating Greases in Rolling Point Contacts
Impact of water on EHL film thickness of lubricating greases in rolling point contacts (full article)
Water in oil contamination
Water in oil
Water in oil
Strategies to achieve and sustain dry oil
How should I remove water from my oil reservoir?
Best ways to remove water from oil
Removing water contamination from oil
How to determine water in oil (brief)
Best ways to test for water in oil
Karl Fischer methods
Arizona Instrument - Relative humidity test
Guide to measuring water in oil
Spectro FluidScan alternative to Karl Fischer (2014)
Water in oil: How does the laboratory determine this?
HY-PRO - Removing dirt and water using vacuum dehydrator

SKF recommends a conservative 200 ppm limit of water content. This can be achieved with desiccant breathers and proper water removal techniques (vacuum separation, centrifugal separation). Most circulating systems have tanks to allow some standing time to promote separation.

Some greases and oils can carry as much as six percent water when mobile. Water separates readily at a standstill and displaces oil on metal surfaces - attacking metal surfaces directly. Avoid standstills with water in the system if possible.

A good way to get an estimate of the concentration of water in oil is to use the calcium hydride method. There are different suppliers and variations on how to do this. The basic concept is that you put some oil and kerosene into a vessel. The instrument that you buy will have this vessel as a part of it. A calcium hydride capsule is placed in with the kerosene and oil. The vessel is then sealed and agitated.

In humid environments, condensate can form in rolling-element bearings and cause corrosion, leading to a reduction in bearing life. The condensed moisture's effect can be reduced by carefully choosing the grease lubricant. Greases thickened with sodium soap will absorb (emulsify) large quantities of water but may soften it to such an extent that the grease flows out of the bearing. Lithium soap greases do not emulsify water but with suitable additives can provide good protection against corrosion.

Although grease can absorb large quantities of water, separation occurs due to pressure and shear, leading to free water. This does not have an impact on the film thickness under fully flooded EHL conditions. However, water does have an effect on the film thickness under starved conditions where the differences are related to the change in oil bleed. In the presence of water, an increase in oil bleed was found for lithium, lithium complex and polyurea grease. These greases showed a reduction in the levels of starvation and, therefore, thicker films. Water contamination led to lower oil bleed for calcium sulphonate complex greases, which led to an increase in starvation, and therefore, thinner films compared to their uncontaminated counterparts.

Maintenance strategies - reactive, preventive, predictive and proactive

Best ways to prevent equipment problems (2016)
3 easy steps for proactive maintenance (short video 2018)
9 principles of modern maintenance (2018)
Bill Keeter - P-F interval: Real or imaginary?
P-F curve and reliability centred maintenance
Understanding the P-F curve and its impact on reliability centred maintenance
Predictive and proactive maintenance (short video, 2018)
John Day, 1997 - Proactive maintenance (slides)
Proactive maintenance: 3 steps (short video)
Abnormality reporting key proactive maintenance
Predictive vs. preventive maintenance: which is the right one for your business?
Predictive maintenance: expensive but worth it
Used-oil analysis for predictive maintenance
Predictive maintenance: 8 keys to a successful implementation
Unleash the power of predictive analytics! Can your machine tell you when it will fail?
What comes after predictive maintenance?
Securing your future with proactive maintenance
Making the transition to proactive maintenance (2016)
Predictive maintenance expensive but worth it (2016)
Predictive maintenance vs preventive maintenance: Which strategy for your company? (2017)

Combining effective failure analysis with a good predictive maintenance program usually results in huge benefits. Depending on the type of facility, it can not only reduce maintenance costs by 20-30 percent but also increase production by similar values. However, it does require a cultural change.

Predictive is not divining
Why proactive maintenance is key for a world-class lubrication program
Proactive maintenance at Weyerhaeuser - putting the theory to test
How to implement effective maintenance planning and scheduling
Day in the life of a proactive maintenance planner
Quant - Industrial maintenance today and future trends (Proactive)
Why proactive maintenance is key for a world-class lubrication program
What a maintenance reliability program should look like
Maintenance 4.0
Mobility Work - Next-gen maintenance in the context of industry 4.0 and IOT (2018)
Mobility Work - 5 keys to choose your CMMS software (2018)
Ricky Smith - When preventive maintenance doesn't work
Ricky Smith - Preventive maintenance - Where are you? (2017)
5 corrective and preventive maintenance levels (2016)
Loctite - Make reliability-centered maintenance a top priority
Preventive maintenance
Download R. Keith Mobley’s Reflections on Excellence

The cost of a reactive maintenance program can be up to 10 times that of a proactive approach.

Data proliferation: There will be a mountain of data types with the advent of holistic CM and the varied techniques and disciplines utilized. Powerful intelligent agents (IA) will be needed. That means that manual evaluation would be almost impossible and add unnecessary risk of missing subtle patterns.

Reliability Centred Maintenance (RCM) was originally called On-condition Maintenance, a term coined by the commercial airline industry. Three surprising discoveries were made:
(1) Scheduled overhaul has little effect on the overall reliability of a complex item unless the item has a dominant failure mode.
(2) There are many items for which there is not an effective form of scheduled maintenance.
(3) Preventive maintenance actually increased the rate of failure in some cases. Scheduled maintenance tends to increase breakdowns, and this can only be because it is doing harm by disturbing a relatively satisfactory state of affairs.

Internet of things (IoT)

With the implementation of computerized maintenance management systems (CMMS), the manufacturing industry became incredibly more efficient. A CMMS tracks system maintenance, inspections and breakdowns, making system disruptions smaller and even obsolete. Instead of manually tracking problems or changes on a piece of paper, a CMMS handles all of this remotely, increasing productivity. The benefits include fewer repairs, lower maintenance costs, a streamlined workforce, and historical data and trend reports.

CMMS technology also connects devices remotely, allowing them to "talk" to each other. Often referred to as the Internet of Things (IoT), it connects factories to the Internet, enabling automation and remote monitoring. Rather than a manual check, the IoT allows systems to be connected to each other and essentially monitor each other's process.

With this connection, plants can easily collect and aggregate big data, or a mass of information concerning their systems. This information can be measured and analysed to increase productivity and efficiency. The IoT helps manufacturers work better by getting products to consumers faster.

Dr. David Almagor - Will IIOT technologies replace factory maintenance workers? (2018)
National Instruments - Online asset monitoring software (2018)
IIoT for predictive maintenance applications (2018)
Smart automation tools unlock competitive advantage in lubricant technical service (Must read article, 2017)
Why you should try smart maintenance (2018)
Maintenance 4.0

Management, maintenance management, lubrication excellence

5 ways to drive innovation in manufacturing (2018)
How to manage and benefit from change
A tactical approach for improvement
An effective way to drive improvement
Executing a continuous improvement plan
Partnering for continuous improvement
Create, implement improvements daily
The road to prescriptive maintenance
Strategies to manage asset performance (2018)
8 steps to better Kaizen results
4 common maintenance problems (2016)
Noria case studies
Measuring the financial impact of a successful lubrication program (2016)
Why should managers care about oil?
How proper lubrication can enhance your plant's reliability (2017)
Autonomous maintenance: 5 steps to successful implementation
5 corrective and preventive maintenance levels you need to learn about
6 elements of a successful preventive maintenance programme (2017)
The power of maintenance KPIs (2017)
Key factors to a better industrial management
How to define world-class maintenance
Maintenance 4.0
Noria - How to cost justify a lubrication program (2018)
A lubrication program - By using the Five Rights, you won't go wrong
Noria - Plan, develop and implement a lubrication programme (webinar)
Lubrication program to cut downtime
Best lubrication program - AB InBev (45 minute video, 2018)
Why your lubrication program needs a champion (2015)
6 keys for a reliability-centered lubrication program
How to equip lube technicians for success (2015)
Recoila - Lubricants are crucial to the safe, reliable, efficient functioning of all machinery
The business case for proper lubrication
5 ways to reduce lubricant spending
Condition-based vs. interval-based oil changes (with Oil Change Wizard, 2001)
The state of the lubrication in USA (Comment: It is even worse elsewhere)
Signs you are in the real world of maintenance
Three pillars of world-class maintenance
UE - Three quick tips on maintaining lubricant quality (short audio)
Why are we failing to convince consumers of the need for high quality lubricants? (2017)
Selling lubrication excellence to management (2004)
The business case for lubrication excellence
Kluber - Lubrication best practices/
9 steps to best in class lubrication
LE - Why most lubrication improvement programmes fail and 5 Rs are no longer enough
Reliability case studies
Machine modifications that increase reliability
Applying Lean Six Sigma methodology
Applying Lean Six Sigma principles to lubrication
Using lean principles to make your plant cleaner and more efficient (2018)
The lean manufacturing techniques
How to optimise the state of lubrication
Optimize machine health with precision lubrication
Precision lubrication
Secrets to becoming a world-class PM facility
Communicate to build world-class culture
Remedies for a bad maintenance culture (2015)
How to change your maintenance culture (2018)
Communication key for a successful lubrication programme
Employ 'Standard work' in maintenance
5 tips for greater workplace efficiency
2 keys for organisational effectiveness
Achieving effective machinery lubrication

Training, education, skills

Elevating the status of lubrication personnel
Why train for machinery lubrication?
ICML certification (2018)
Why train for machinery lubrication? (2011)
You need a lubrication skill development programme
Why education is the secret to successful change (2016)
Increase training to improve results
TESTOIL webinar schedule
Reliability web - Articles
TPM (Total Productive Maintenance), India - Articles
CMMS - How to plan your maintenance (2016)
Maintenance: Time and staff optimization analysis (2016)
Best practices for maintenance supervisors
Inspection 2.0: The cornerstone of world-class TPM (Total Productive Maintenance) (2016)
Achieving total productive maintenance without supervisors
Hazards of changing lubricant brands
How to transition to a new lube supplier
How lubricant suppliers impact machine reliability
Successful implementation of computerised maintenance management system (CMMS)
Lubrication for hire: Is contractor-based lubrication right for you?
Advantages of contracting out your lubrication programme
How to manage lubricant waste and disposal
Maintenance glossary
Wikipedia - What is REACH?
Why Smart Manufacturing is a dumb idea

Reliability resolutions for improving operations and maintenance:

1. We will provide leadership and communication about organisational changes.
2. We will train in best practices and provide on demand refreshers.
3. We will expand our maintenance planning into day-to-day tasks.
4. We will keep our schedule updated 4 weeks in advance.
5. We will solve problems and eliminate reoccurring failures.
6. We will capture both useful data and site knowledge.
7. We will let the equipment talk to us via the condition based tools.

Last word

The machine and the lubricant can telegraph hints and signals to us in a variety of ways, but only if we are both tuned in and literate to their message. Tuned in means being vigilant and ubiquitous, like a detective, always looking for clues even when camouflaged from view. Literate means not only recognising the presence of the clue but also being wise to the meaning of its message and the corrective response.

Condition-based maintenance is based on identifying measurable criteria that allows the time to plan for early intervention on failures, thus helping to reduce catastrophic and secondary damage. The earlier you are able to detect the failure, the more time you will have to prepare the spares, ensure labour resources and communicate the need to everyone.

A best practice tends to spread throughout an industry after a success has been demonstrated. However, demonstrated best practices can often be slow to implement, even within an organisation. The three main barriers to adoption of a best practice are a lack of knowledge about current best practices, a lack of motivation to make changes for their adoption, and a lack of knowledge and skills required to do so.

Light reading

The term tribology was mentioned for the first time in 1966 in the Jost Report, a study commissioned by the British government to investigate damage from wear. The committee headed by Peter Jost, estimated that application of basic principles of tribology could save the UK economy approx. ₤ 515 million per annum.

Origins of Reliability Centered Maintenance (RCM)
Nancy Regan - Lessons from a master: The most valuable RCM business and life lessons John Moubray taught me (50' video, 2017)

The most influential mentor of my career died on January 15, 2004. Thirteen years later, John Moubray’s wisdom continues to serve me. If you have anything to do with Reliability Centered Maintenance (RCM), then you know who John Moubray was. No matter what your perspective is on RCM2, there’s no denying that John was a giant in the RCM world; he was a fierce proponent of the RCM philosophy designed by the original architects, Nowlan and Heap. He trained his network members to be responsible custodians. John said it best when he affirmed: we are here to promulgate the principles we believe to be best practice and in so doing make the world a safer place for all who live in it. In 1997, by luck (or Providence), I stumbled upon Aladon LLC and the RCM2 process, and thus began my journey into RCM. John Moubray became my mentor. This presentation summarizes the most important RCM lessons John delivered about the process he described as “majestic.” However, a keen entrepreneur, John’s wit and wisdom extended beyond RCM. This presentation also features his insights on business and life that are just as relevant (if not more relevant) today as they were nearly twenty years ago. Ever-grateful for the treasure of John Moubray’s philosophy, the presentation ends with the most valuable advice he ever gave me – advice that applies to everyone (and has nothing to do with RCM!). Nearly two decades later, I finally get it!

The crude oil fractional distillation
Houghton International - The Houghton Line periodical (big document)
Common sales myths
Riding the Film - 1937 Chevrolet engine lubrication (11 minute video)
Tribonet - History of tribology (2016)
Tribonet - Ancient tribology artifacts looted?

Dictator of Equatorial Guinea, Francisco Macias, banned the use of lubricants in the Malabo city power plant, claiming that he has magical powers. The plant exploded.

Now seriously

Some time ago the International Fluid Power Society produced a webinar on the prevention and management of fluid injection injuries. It cited a study by Snarski and Birkhahn, two emergency department doctors at the New York Methodist Hospital, which contained some very sobering statistics:
* Fluid injection injuries are relatively rare with around 600 incidences in North America per year. That's the good news. The bad news is it means your average emergency department doctor may not recognize the seriousness of the situation.
* High-pressure grease guns/systems account for 57% of injection injuries. Paint, hydraulic oil and similar fluids account for 18%. And diesel fuel injectors 14%.
* The overall incidence of medical amputation resulting from such injuries is 48%. But if the injection pressure is greater than 7000 PSI, the amputation rate approaches 100%.
* The average elapsed time between occurrence of injury and seeking medical attention is 9 hours. This is attributed to the apparent benign nature of initial injection, combined with a lack of awareness of the seriousness of this type of injury.
* Disturbingly, where 10 hours or more elapses between occurrence of injury and medical intervention, the amputation rate approaches 100%.
Bottom line: fluid injection injuries are medical emergencies which typically require surgical intervention to release the injected fluid and limit the tissue damage it causes. This is something everyone who works on or near hydraulic machines needs to be aware of.
(Brendan Casey)

Please click here to e-mail to me any addresses that no longer work. Thank you! Petr Vavruch Go to top

Quotes are from many different sources - sorry for not to be able to acknowledge them, thank you all!

 Revision 9 August 2018