Gasoline from A-80 to AI-98
April 7, 2011
Modern automobile gasoline must meet a number of requirements that ensure efficient and reliable operation of engine and operating requirements: to have good evaporation that enables to get homogeneous air-and-fuel mixture with optimal composition at any temperatures; to have hydrocarbon-type content that ensures stable and non-knocking combustion process in all engine operation conditions; not to change its composition and characteristics during long-term storage and to have no negative influence on parts of fuel system, containers, mechanical rubber parts and so on. Ecological fuel properties are advanced to the forefront in recent
Assortment, quality and composition of automobile gasolines
Most automobile gasolines in Russia are produced under standard GOST 2084-77and GOST Р51105-97 and TC 38.001165-97. Depending on octane number GOST 2084-77 provides five brands of automobile gasolines: А-72, А-76, АI-91, АI-93 and АI-95. Numbers in first two brands indicate octane number determined by motor method, and the latter – by research method. In view of increase of motor cars share in the whole automobile park there is appreciable tendency of reduction in demand for low-octane gasolines and increase in usage of high-octane gasolines. Gasoline A-72 is almost not produced because of absence of facilities that work on it.
There is greater demand for gasoline А-92 that is produced under TC 38.001165-97, although share of gasoline А-76 in the whole production is still quite high. Mentioned technical conditions also provide gasoline brands А-80 and А-96 with octane numbers according to the research method respectively 80 and 96. These gasolines are intended mainly for export supplies. Gasoline АI-98 with octane number 98 according to the research method is produced under ТC 38.401-58-122-95 and ТC 38.401-58-127-95. Gasolines А-76, А-80, АI-91, А-92 and А-96 are admitted to be produced with the use of ethyl fluid. Little-ethylated gasoline АI-91 with content of lead 0,15 g/dm3 is produced under special technical conditions (TC 38.401-58-86-94). The use of alkyl-lead antidetonators is not allowed during the production of gasolines АI-95 and АI-98.
Requirements of GOST 2084-77 to the quality of automobile gasolines are shown in the table. All gasolines produced under GOST 2084-77, depending on the evaporation indexes, are divided into summer and winter. Winter gasolines are intended for use in the north and northeast regions during all seasons and from the 1st of October to the 1st of April in other regions. Summer gasolines are intended for use in all regions except north and northeast regions in the period from the 1st of April to the 1st of October: summer gasoline is admitted for use during all seasons in the south regions.
Parameters of automobile gasolines produced under GOST 2084-77 differ essentially from established international norms, especially in regard to ecological requirements. GOST Р 51105-97 “Fuels for internal-combustion engines. Unleaded gasoline. Technical conditions.” was developed for the purpose of competitive growth of Russian gasolines and bringing them to the level of European standards, it was implemented since 01.01.99. This standard does not replace GOST 2084-77, that provide the production of leaded and unleaded gasolines. Only unleaded gasolines (maximal lead content is not more 0,01 g/dm3) will be produced under GOST Р 51105-97.