The viscosity 20W50 - An oil for warm areas
The viscosity is one of the most important physical characteristics of an engine oil. She describes the flow properties, the viscosity class in the choice of a suitable oil is crucial. When a certain flow resistance as the viscosity 20W50 appropriate depends largely on the ambient temperature.
What is viscosity?
Viscosity is in addition to the quality an important Kritierium choosing the right motor oil. The oil viscosity must correspond to the respective ambient temperatures. If the oil in a cold engine too tough, it can not be moved. Will it turn hot engine too thin, the oil can not protect sufficiently the engine parts. An optimization in terms of viscosity helps to increase energy efficiency and to prevent component wear. A motor oil, such as for example a 20W50 oil is then suitable for the vehicle, if it can flow sufficiently well in the cold state and at high ambient temperatures is thick enough to protect the components of the engine.
What does the viscosity class "20W50"?
For multigrade oils such as 20W50 oil viscosity is characterized by two numbers. The first number in front of the letter W - the 20W50 oil, this is the 20 - describes the resistance to flow of the oil at lower temperatures ( "20" means: operable to a minimum of 0 degrees Celsius). So you are an indication of how the viscosity of engine oil is assessed at winter temperatures. The number after the W provides information on the oil viscosity at high ambient temperatures. The larger the number, the more viscous the oil remains at high outside temperatures. With a viscosity of 20W50 the entstprechende number 50 is ( "50" means: functional up to 50 degrees Celsius). Sufficient viscosity is thus given for a 20W50 oil at a temperature range of 0 up to 50 degrees Celsius.
If the viscosity is not a quality characteristic, but rather the key indicator of the viscosity of an oil. It describes the ability of the engine oil, establish a separating lubricant film between two moving engine components. A viscosity as 20W50 is properly selected when the oil at the given temperatures neither too thin is too thick.