Clean surface in engine oils

Recently, a report was given to one of the industries by one of the country’s industry reference laboratories, stating that the clean level of the engine oil you use is 8 on the NAS scale, which is contaminated in this respect. It is recommended to prepare the oil with a clean level of 6.

This report seems logical at first glance. Engine oil must have a good level of cleanliness, otherwise the entry of pollutant particles between the surfaces involved in the engine will increase the wear of the surfaces. But in a deeper look, it should be said that as soon as the oil is used in the car engine, the entry of high amounts of pollution from combustion into the oil causes high pollution in the engine oil and raises its cleanliness level above 12 on the NAS scale. He said that the clean level of engine oil is not so important for car manufacturers.

Examination of automakers’ records also proves that most automakers use advanced filtration systems, even centrifugal systems, to reduce oil contamination during operation. However, none of them required a clean level below 10 for the car.

Even diesel manufacturers such as Scania and Volvo, which have found even micron-sized particles in diesel fuel to be problematic, have taken a different stance against engine oil.

However, in one of the applications of engine oil, which is used in compressor systems, the importance of oil cleaning code increases. In compressors that use engine oil as an alternative to circulating oils or VDL, the acceptable cleanliness level is around 5 to 7 on the NAS scale. For this purpose, car oil for use in such compressors must be subjected to primary filtration by self-equipping or a secondary filtration system to reach the desired level of cleanliness.