Glossary
A
ACEA
Association des Constucteurs Europeens d"Automobiles
Additives
Additives are oil-soluble substances which are added to the mentioned base oils. They chemically and/or physically change or enhance the properties of lubricants.
Chemically active additives:
• Detergents
• Dispersants
• Antioxidants
• Wear-protecting additives
• Corrosion inhibitors
Physically active additives:
• Viscosity index modifier
• Pour point modifier
• Friction characteristics modifier
All-Year Oils
They are also known as multigrade oils and can be used in our temperate climate over the whole year. These fluids are not too viscous during the winter and does not become too thin at high engine temperatures, like e.g. 0W-30, 0W-40, 5W-30, 5W-40, 10W-40, 15W-40, 20W-50.
Anti-Wear (AW) Additives
With the help of appropriate additives, it is possible to establish an extremely thin layer on slides; its shearing strain stability is significantly lower than that of metals. This layer is solid under normal conditions, but turns lubricant under wearing conditions (pressure, temperature). This way excessive wear (galling or welding) can be prevented. If required (a metal/metal contact), the film is continuously renewed by means of a chemical reaction.
Antioxidants
Under the influence of heat and oxygen, lubricants tend to oxidise (ageing). This corrosion process is accelerated by acid combustion products and traces of metals which have catalytic effects (abrasive or corrosive wear). The result is deterioration, which entails the development of acid as well as lacquer, resin, and sludge consistent deposits; these are insoluble in oil (e.g. like oil carbon). By adding antioxidants, ageing protection can be enhanced significantly. Though they cannot entirely prevent ageing process, antioxidants demonstrably decelerate it.
Substances for ageing protection can be effective in three ways:
• Scavengers (against primary ageing effects): Radicals are chains of carbonic hydrogen which possess free valences due to a breach in the chain or breaking out of hydrogen atoms. Oxygen immediately attaches itself to these spots (oxidation). By transferring hydrogen from the additive to the chemically active spot, scavengers saturate (repair) these “gaps”.
• Peroxide decomposers (against secondary ageing effects): They are fully effective not sooner than ageing substances (oxygen compounds) have developed. Peroxide decomposers detract oxygen and create harmless compounds.
• Passivators / Metal-ion deactivators: They cause passivating of iron and copper particles and thus stop or lessen the catalytic influence these metals have on the ageing process. Passivators clasp around metal ions in oil so that they have almost no catalytic activity at all.
API
American Petroleum Institute
ATF
Automatic Transmission Fluid
Automatic Transmission Fluid (ATF)
ATFs are especial lubricants that meet extraordinary high demands of automatic clutch and transmission systems. These require a very good viscosity and thermic characteristics, shearing strain stability, high resistance to oxidation, outstanding frothing and air-releasing properties, defined friction characteristics, EP characteristics, etc.
B
Base Oils
Base oils bestow on lubricants their fundamental specific characteristics, which noticeably influence the performance of the end products.
Base oil products are distillation and raffination products that are extracted from mineral raw material – petroleum – and consist mainly of saturated hydrocarbons, sometimes with small percentage of unsaturated hydrocarbons.
Hydro-cracking oils are refined mineral oils of high purity and with the enhanced molecular structure.
Poly-alpha-olefins (PAO) are products of petroleum chemistry (synthesis). They are chemically created straight-lined compounds of hydrocarbon.
Synthetic esters are compounds of synthetically created acids with alcohols. They are chemically made products with molecules of every form, structure, type, and size.
BIA
Boating Industries Association
BMW
Bavarian Motor Works
C
CCMC
Comité des Constructeurs d"Automobiles du Marché Commun
Corrosion Inhibitors
Generally speaking, corrosion is a chemical or electrochemical affect on metal surfaces. As a protection against corrosion, additives that act on interfaces qualify best; these can be either ash-free or ash-producing. The products of polar group attach themselves to metal surfaces, while the rest of alkyls build up thick, fur-like, hydrophobic (water-resistant) barriers. Due to their polar structure, corrosion inhibitors compete with the EP and AW additives, meaning that the effectiveness of the latter can be thus affected.
D
Detergents
Detergents are washing substances that counteract formation of deposits on the component parts exposed to high temperatures. Detergents virtually keep the engine clean. Moreover, they build up alkaline reserves in the engine oil, so that acidifying combustion products can be neutralised.
Detergents are ash-compounding (metalorganic) additives, which prevent depositing of solid dirt particles on metal surfaces (agglomerating).
Diesel Engines Oils
At present, the highest requirements on lubricants for conventional and supercharged diesel engines are presented by the classifications ACEA B3 and B4 as well as the clearance VW 505.00. Such oils are optimally suitable for use in self-priming or supercharging diesel engines with or without charge air cooler. High-performance engine oils alone meet these demands, like our Bizol Diesel Ultra SAE 10W40.
DIN
German Standard Institute
Dispersants
The dispersants’ task is to envelope solid and liquid particles (e.g. dust, water, combustion products, oxidation products) and to keep them dispersed and in suspension to avoid deposits.
The process of peptization: It refers to enveloping of solid particles in oil and keeping them in suspension by means of ash-free (organic) dispersants.
The process of solubilisation: Enveloping and keeping in suspension of fluid particles (water, acids). No neutralisation.
DOT
Department of Transportation
DPF
Diesel Particulate Filter
E
Einbereichsöl
Erfüllt ein Öl nur die Anforderungen einer SAE-Klasse, so ist es ein Einbereichsöl, z.B. SAE 10W, 30, 50 bei Motorölen oder SAE 80W, 90, 140 bei Getriebeölen.
EMA
Engines Manufacturer Association
Engine Oils
Engine oils are used to lubricate bearings, driving gear, cylinders and the steering wheel for the internal combustion engine; they are classified according to their viscosity characteristics (SAE classes); there are non-alloyed and alloyed engine oils.
The present-day engine oils, their types and special characteristics, are based on different base oils or base oil mixtures. Complementarily, additives are used according to the intended effect. Only a well-balanced formulation (base oil with additive substances) gives a high-performance engine oil.
Extreme Pressure- (EP-) Additive
The oldest EP additive is pure sulphur. The EP and AW additives are substances that are active on interfaces; additives of polar group usually contain different combinations of the elements zinc, phosphor, and sulphur. The best-known representative of this kind is zinc dithiophosphat (ZDP), which is also effective for preventing ageing and corrosion.
The EP additives are mixed to transmission, engine, hydraulic system, metalworking oils in order to increase their bearing pressure properties and to decrease wear in the areas with mixed friction. The effect is based on establishing layers on surfaces (metal surfaces). They are supposed to prevent welding of rough spikes in the areas with mixed friction characteristics and to grand possibly wearless sliding of contacting metal surfaces. The reducing of friction is also desirable.
F
FIAT
Fabbrica Italiana Automobili Torino
FMVSS
Federal Motor Vehicle Safety Standard
Friction Modifier
Friction modifiers (FM) are additives that lower friction and are only effective in areas with mixed friction rates. On surfaces, the active substances create fur-like layers (physical process) which are able to keep metal surfaces separated. The FM are very polar, i.e. they possess high affinity to surfaces in connection with friction-preventing properties.
Fully Synthetic Engine Oils
Synthetic base oils provide a basis for the engine oils with significantly enhanced properties. Fully synthetic engine oils can be added into petrol and diesel engines and provide an optimum wear protection, excellent oil supply at the cold start, smooth engine running, and outstanding cleanliness of an engine. They often fulfil the highest requirements API, ACEA and comply with the clearances by most engine manufacturers. Especially suitable for long intervals between oil changes. Typical viscosity classes: 0W-30, 0W-40, 5W-40.
G
GL
Gear Lubricant
H
HTHS
High Temperature High Shear
Hydraulic Oils
They are ageing-resistant, low-viscosity, not frothing, highly refined fluids extracted from a mineral oil with low pour point. Used in hydraulic systems, predominantly with hydrostatic drive. They can also be used in a system with hydrodynamic drive as long as they meet its requirements.
Hypoid Gear Oils
Extreme pressure lubricants with EP additives that enhance lubricating qualities and prevent corrosion. Mainly used for axle drive in vehicles that have spiral bevel gears and offset gears (hypoid gears).
I
ISO
International Organization for Standartization
J
JAMA
Japan Automobile Manufacturers Association
JASO
Japanese Automobile Standard Organisation
K
Kinematic Viscosity
The ratio of dynamic viscosity to density at a given temperature. Measure: square millimetre per second [mm²/s], previously centistokes [cSt].
Kinematic viscosity = dynamic viscosity / density
M
Mineral Engine Oils
Engine oils are usually manufactured of mineral oils. Yet these oils have insufficient performance in terms of ever higher requirements such as extended intervals between oil changes, high engine performance, demands of smooth and noiseless engine running, etc. Typical viscosity classes: 10W-40, 15W-40, or 20W-50.
Modifiers
The use of VI modifiers (VI = viscosity index) enables manufacturing of multigrade engine oils. The VI modifiers increase or elongate the viscosity of a particular oil and thus enhance its viscosity-temperature properties.
Multigrade Oils
If an oil meets the requirements of both a W-class in a cold state and a class without “W” at 100°C, it is referred to as a multigrade oil, e.g. SAE 0W-30, 10W-40, 15W-40 for engine oils, or SAE 75W-90, 80W-90, 85W-140 for transmission oils
N
NMMA
National Marine Manufacturer Association
O
OEM
Original Equipment Manufactures
P
PAO
Polyalphaolefin (Synthetic hydrocarbon as a basis for engine oil. Source product - ethen.)
PIB
Polyisobuten (Synthetic hydrocarbon as a basis for engine oil. Source product - buten)
Pour Point Modifier
Pour point is the lowest temperature (in degree Celsius) at which an oil is just pouring. Solidification of a particular oil is determined by paraffin waxes in the base oil, which begin to crystallise at low temperatures. The addition of substances that reduce the pour point protracts this process and enhances the low temperature characteristic of oils.
PSA
Peugeot Société Anonyme
R
Retarder
is a device used to augment or replace some of the functions of primary friction-based braking systems of (usually) heavy vehicles.
S
SAE
Society of Automotive Engineers
SAE Classes in General
Engine and transmission oils for vehicles are characterised by SAE classes, which have also been transferred to the according DIN standards. The following is determined by them: temperatures for viscosity measuring, viscosity threshold values and attribution of classes. Oils that are attributed viscosity threshold values for cold state additionally get the letter “W” (for “winter”) in their classification.
As for hot state, viscosity of engine and transmission oils is determined at 100°C, uniform for all SAE classes. However, this does not come up to real-life conditions of engine oils, thus in many cases, viscosity at high temperatures and under high shearing strain (HTHS ) is additionally appointed to engine oils.
SAE Classes for Engine Oils
Following classes are standardised: 0W, 5W, 10W 15W, 20W, 25W-20, 30, 40, 50, 60
SAE Classes for Transmission Oils
Following classes are standardised: 70W, 75W, 80W, 85W-80, 85, 90, 140, 250
SAPS
Sulphated Ash, Phosphorus, Sulphur
Semi-Synthetic Engine Oils
These are mineral oils with synthetic components. They enhance the cold start performance, keep the engine clean, and provide an outstanding wear protection. Typical viscosity classes: 10W-40, 5W-40.
SHPD
Super High Performance Diesel
Smooth-Running Engine Oils
They have an advantageous flowing characteristics at low temperatures and high thermic stability, and need less pumping. Hence, they have a positive influence on fuel consumption. Typical viscosity classes: 0W-30, 0W-40, 5W-40, 5W-30, 10W-40.
STOU
Super Tractor Oil Universal
T
TASA
Typi A Suffix A
TC-W3
Test Cycle Watercooled 3
TOU
Tractor Oil Universal
TWC
Three Way Catalyst
U
UHPD
Ultra High Performance Diesel
UTTO
Universal Tractor Transmission Oil (obsolete)
V
VI
Viscosity Index
Viscosity
Viscosity is the capacity of a fluid to provide resistance and thus friction to an opposite laminar movement of two adjacent layers. Having a high viscosity means being viscid, whereas a low viscosity is used synonymously to thin fluid.
In short, viscosity can be described as flow resistance.
Viscosity strongly depends on temperature. The indication of the viscosity range for a multigrade oil (e.g. 10W-40) specifies the oil performance at high and low temperatures. The number before the W (10) stands for the viscosity at low temperatures (40°C), whereas the number after the W (40) indicates the viscosity at high temperatures (100°C).
There is a distinction made between the dynamic viscosity (measured in Pa s) and the kinematic viscosity (in mm2/s = cSt), the last one being the quotient of dynamic viscosity and density. Like density, viscosity also depends on temperature and pressure.
The viscosity index of a fluid is determined by its viscosity measured at 40°C and 100°C.
Viscosity was the basis for the first classification system for engine oils in 1911 and was defined in the SAE classification system. Today, viscosity is still one of the most important characteristics of an oil. The development of testing procedures which could better predict the motor behaviour has resulted in viscosity measurements (DIN 51511) at different temperatures and velocity gradient.
Viscosity Classes
Viscosity is the best-known characteristic of lubricating oils. It is the measurement for the inner friction of an oil when flowing. When an oil is cold, its inner friction is high (high viscosity). The warmer the oil, the lower its inner friction will be (low viscosity).
Changes in viscosity conditional upon temperature can vary from oil to oil and are characterised by the viscosity index (VI), a non-dimensional numerical value. Single-range oils have the VI about 100, multigrade oils – up to 150, depending on its range.
Viscosity Index (VI)
Viscosity of every oil changes according to its temperature. It will be decreasing when the temperature is rising, and increasing when the temperature is declining. Viscosity index is a characteristic for the viscosity/ temperature performance of oils. The higher the number, the less the viscosity of a particular oil will change at temperature variations. The less its viscosity changes conditional upon temperature, the better an oil is suitable for practical use.
Viscosity-Temperature Modifiers
Metaphorically speaking, they are very long, fibre-like molecules that are existent in oil and are conglomerate when cold; they offer relatively low resistance to the movement of oil molecules. With increasing temperature, they loosen, take a bigger volume, and create a meshed network that slows down the movement of oil molecules and protracts a too quick thinning-out of oil.
Z
ZF
Zahnradfabrik Friedrichshafen (Gearwheel factory)