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Types of lubricants
The various lubricants automotive, they come from mixing base oils and chemical additives in specific ratios, formulas, that ensure the requirements of the specifications of the engines and the machines they have to lubricate.
The following categories of lubricants are available on the market:
Mineral base oils or mineral oils (mineral):
is a mixture of mineral base oils, made from crude oil which has been subjected to a variety of complex separation processes (refining). They are used quite often, in cars and in industrial applications.
Semi-synthetic (Semi-Synthetic) base oils:
is a mixture of mineral base oils, or hydrogenated base oils, synthetic base oils and chemical additives. Semi-Synthetic is a mixture of oil usually 70-80% mineral oil and 20-30% synthetic oil. It is of better quality than mineral oils.
Synthetic lubricants:
It is a mixture synthetic base oils and chemical additives. It is the best available in lubricant technology today.
Viscous lubricant (SAE)< /p>
This property shows the oil's resistance to flow. It shows i.e. how thin or thick the oil is. There are various units for measuring viscosity. A unit that is accepted by all countries is the centistoke. An oil has a viscosity of one centistokes when its resistance to flow behaves like water at a temperature of 20°C.
The change in viscosity is inverse of the temperature, i.e. the higher the temperature, the lower the viscosity. In order not to cause confusion, today an oil fluidity scale has prevailed that applies to the whole world. This is known by the initials SAE (Society of Automotive Engineers) and is known as the American Society of Automotive Engineers.
Calibration of lubricants according to their viscosity and use
The calibration of lubricants also follows specific international standards. So the calibration of the oils refers to:
According to the SAE calibration there are single-grade or monotype oils and multi-grade (Multi-grade) or multi-type lubricants:
Single-grade are called the lubricants that adjust the viscosity (or their fluidity) in a small range of temperatures (e.g. SAE 10W, SAE 30, SAE 90).
Polytypes are the oils that adapt and maintain their fluidity in a wide range of temperatures (e.g. SAE 10W/40, SAE 20W/50, SAE 75W/90).</p >
The prefix W (Winter) refers to the flow characteristics of the oil at low temperatures.
Classification based on the certification origin of its specifications
Depending on the certification body of the lubricants are classified into categories with key players in API, ACEA. Let's look at their terminology.
The initials ACEA (ACEA - European Automobile Manufacturer's Association) refer to the specifications for oils established by the Association of European Automobile Manufacturers.
The initials API (American Petroleum Institute) refer to the specifications for oils established by the American Petroleum Institute.
Manufacturers' Specifications refer to specifications established by the manufacturers. The above specifications are completely acceptable by the car manufacturers and oil manufacturing companies.