VNIINP-50-1-4u oil is a high-quality synthetic diether oil obtained by chemical synthesis. It contains a composition of effective additives and, in terms of operational characteristics, outperforms VNIINP-50-1-4f oil. The oil has high (up to 200°C) thermo-oxidative stability with an allowable overheating up to 225°C.

Thanks to its exceptionally efficient viscosity-temperature properties, the VNIINP-50-1-4u oil forms a very strong film on friction surfaces at operating temperatures above 100°C, which does not break down even in the most extreme thermal conditions. Additionally, with a low freezing point of -60°C, it can be effectively used in extreme conditions of harsh winters. It is intended for modern gas turbine engines and new prospective equipment.

The VNIINP-50-1-4u oil is fully compatible with the VNIINP-50-1-4f oil and can replace it without requiring replacement of structural materials and rubber.

The VNIINP-50-1-4u oil mixes well with mineral oils. With its high dissolving ability, the oil can dissolve sludge and varnishes, remove deposits that have formed in the engine as a result of the use of other oils, and maintain the cleanliness of engine parts.

The VNIINP-50-1-4u oil has undergone a full cycle of acceptance tests, including flight tests. They have shown that using VNIINP-50-1-4u oil instead of VNIINP-50-1-4f oil significantly increases the engine's working life.

The oil is used as one of the main oils in aviation technology.

It is recommended for prospective equipment.

Technical specifications of VNIINP-50-1-4u oil (TU 38.401-58-12-91)

Indicator name GOST (TU) standard
Appearance Clear, light liquid
Kinematic viscosity, mm2/s:
At 100°C, not less than 3.2
At -40°C, not more than 2700
At -50°C, not more than 8500
Temperature, °C:
Flash point (open cup), not lower than 204
Pour point, not higher than -60
Acid number, mg KOH/g, not more than 0.25
Content of water-soluble acids, bases, mechanical impurities, water Absent
Thermo-oxidative stability, hours at 200°C (air flow rate of 10 dm3/hr) 50
Indicators after oxidation:
Kinematic viscosity, mm2/s, at 100°C, not more than 3.7
Acid number, mg KOH/g, not more than 4.5
Mass fraction of insoluble sediment in iso-octane, %, not more than 0.15
Corrosion on plates, g/m2:
Steel XH15 ±1.0
Copper M1 and M2 ±4.0
Aluminum alloy AK4 ±1.0
Density at 20°C, kg/m3, not more than 926
Tribological characteristics on CHMT at (20±5)°C:
wear rate under axial load of 196 N, not more than 0.45