LUBRICANT COMPOSITION FOR PISTON ENGINES Russian patent published in 2018 - IPC C10M169/00 C10M169/04 C10M133/12 C10M137/04 C10M129/72 C10M105/36 C10N40/25 C10N20/02 

FIELD: chemistry.

SUBSTANCE: invention relates to lubricating compositions for piston engines, in particular to all-season lubricant compositions for aviation piston engines, and is aimed at improving the performance characteristics of a lubricating composition of the required viscosity when used to lubricate heavy-duty parts of aircraft piston engines. Lubricant composition for piston engines contains a base composition and an additive package including antioxidant additives, a dispersant additive based on succinimide, an anti-wear additive and polymethylsiloxane PMS-200A as an antifoam additive, wherein the base composition contains a mixture of two polyalphaolefin oils (PAO), one of which has a viscosity of 10 mm²/s at 100 °C, and the other 125–145 mm²/s at 100 °C, with Syntolux L-6115 ester with a viscosity of 11.5 mm²/s at 100 °C, and the additive package contains as antioxidant additives liquid octylated, butylated diphenylamine and 4-methyl-2,6-di-tert-butylphenol, as the dispersing additive contains succinimide additive LAG-03, as an anti-wear additive – tricresyl phosphate, and further comprises a Syntolux L-439 dibasic acid ester with a viscosity of 3.9 mm²/s at 100 °C as an additive to increase solubility of the additive package in the base oil and corrosion inhibitor 1,2,3-benzotriazole with the following component ratio, wt%: succinimide additive LAG-03 3.5–4.5; liquid octylated, butylated diphenylamine 0.8–1.2; 4-methyl-2,6-di-tert-butylphenol 0.4–0.6; 1,2,3-benzotriazole 0.04–0.06; polymethylsiloxane PMS-200A 0.001-0.003; dibasic acid ester Syntolux L-439 3.637–5.659; tricresyl phosphate 1.3–1.7; PAO mixture 61.9–74.1; ester Syntolux L-6115 14.7–25.9.

EFFECT: higher flash point and lower ash content of the lubricant composition for piston engines while maintaining its high viscosity-temperature, tribological and thermo-oxidative properties.

1 cl, 5 dwg