Manufacture of oil > Base oils > Aircraft oils > Engine oils
In principle, the oils for aircraft piston engines and automotive impose the same requirements. In aircraft engines oils are subject to higher thermal stresses due to the higher liter capacity per unit mass of the engine. However, higher temperatures do not always take place as the oil circulating in the engines, and supplied to the crankcase lodshipnikam from different tanks.
Oil is drawn from the sump pump and returned to the tank through a radiator where it is cooled. Because of the relatively high volume of its oil consumption is supported by a topping of fresh oil. Lubrication and cooling at different ambient temperatures require the use of high-quality paraffinic oils with high viscosity-temperature characteristics.
Oil requirements for aviation piston engines do not change for quite a long period. Therefore, the oil with moderate amounts of additives are burned without the formation of ash deposits, provide trouble-free operation with a time of change obych¬nymi 100-200 flight hours under normal flight conditions.
Also used oil without additives, but for special purposes, such as for running engines. Viscosity of aviation oils vary in the range of 12-25 cSt at 100 ° C. Typical physico-chemical properties of aviation oils are shown in Table.
Oils for civil aviation use as military specifications. Since some indicators of physical and chemical properties determined by laboratory methods can not provide a reliable estimate of the behavior of oils in aircraft piston engines, prior to acceptance to the oil exploitation spend long motor tests.
Viscosity Grade
65 80 100 120 Indicator
Density at 15 ° C, g / cm 0,884 0,887 0,891 0,894 Temperature, 'C:
flash 232 252 266 266
solidification - 29 - 26 - 23 - 23
Viscosity, cSt:
at 40 ° C 80 118 183 282
at 100 ° C 11.7 14.9 20.1 24.8
viscosity index 125 118 116 110
Content,% (wt.):
sulfur 0,30 0,35 0,40 0,45
ash 0.002 0.002 0.002 0.002
Manufacture of oil > Base oils > Aircraft oils > Engine oils