Diesel is a mixture of hydrocarbons which is usually obtained from the processing of petroleum and is mainly used as motor fuel. It starts boiling in the temperature range of 200-350 ° C. For us the following indicators are of high importance: cetane index, cetane number, flash point, cold filter plugging point (CFPP) and the cloud point (CP).
The cetane index and cetane number characterize the combustion of the diesel fuel and its ability to burn. The cetane index is determined by calculation, and cetane number empirically. In case of low cetane number the combustion is belated and burning is quick (the engine starts knocking). In case of high cetane number fuel is quickly ignited and burns at the tip of the nozzle and then is not properly mixed with air (the engine starts to smoke). Cetane number can be increased with impurities. In case of lack of impurities cetane number decreases during prolonged storage of fuel. Therefore, these impurities must be added immediately before the use of fuel.
Flashpoint describes the flammability of fuel and should be above 55 ° C. Even during a small contact of gasoline with diesel fuel the flashpoint is reduced and flammability increases. NB! Be careful when pumping different types of fuel by the same unit.
Cold filter plugging point and the cloud point characterize the possibilities of fuel usage at low temperatures. Paraffins in diesel fuel start to crystallize at low temperatures which causes clogging of fuel filters and cold pipes and can even stop the fuel supply. Fuel with high viscosity has a slow flow.
Diesel Frost resistance:
Summer season diesel fuel in the Republic of Estonia must correspond with the C class, and winter season diesel fuel the 1 class. The summer season in Estonia is considered to be the period from the 1st of May to the 30th of September and the winter season is the period from the 1st of December to the 29th of February. The switching periods are considered to be the periods from the 1st of October to the 30th of November and from the 1st of March to the 30th of April.
Diesel fuel sold at Olerex corresponds with Estonian standards EVS-EN 590.