METHOD OF INCREASING THERMAL-OXIDATIVE STABILITY OF LUBRICATING OILS Russian patent published in 2015 - IPC C10M177/00 C10N30/06 G01N25/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of increasing the thermal-oxidative stability of lubricating oils, in accordance to which samples of lubricating oil are thermostatted by heating in a hermetic cup without mixing for the constant time at atmospheric pressure and fixed temperature, which at each thermostatting of the new sample is step-by-step increased in the range of temperatures, determined by the purpose of the lubricating oil, after heating sampling and testing of the thermostatted samples for resistance to oxidation are carried out. Sampled is a constant weight sample, which then is heated in the presence of air with mixing for a specified time depending on the basic base of the lubricating oil at constant temperature and constant mixing rate, the oxidised samples are photometrically scanned, the coefficient of the light flow absorption is determined, with the determination of the graphical dependence of the change of the parameter of thermo-oxidative stability evaluation on the thermostatting temperature, which is used to determine the optimal temperature of thermostatting, providing maximal resistance to oxidation, characterised by the fact that as a criterion for the evaluation of the thermo-oxidative stability of the lubricating oil taken is a resource of the thermostatted oil work capacity. In the process of testing each new thermostatted sample for resistance to oxidation the sample of the oxidised oil is sampled after equal time intervals, the coefficient of the light flow absorption is determined by photometry, graphical dependences of the light flow absorption coefficient on the oxidation time of the thermostattted oils are built at each temperature of thermostatting, and used to determine the time of reaching the light flow absorption coefficient of the selected value for each oxidised thermostatted oil at different temperatures, the graphical dependence of the time for reaching a selected value of the coefficient of absorption of the light flow of the oxidised thermostatted oils on thermostatting temperature is built with the point of the said dependence with the maximal ordinate, characterising the resource of work capacity being used to determine the temperature of thermostatting, ensuring the maximal resistance to oxidation.

EFFECT: ensuring self-descriptiveness of the increase of the thermo-oxidative stability of lubricating oils and increase of their work capacity resource.

2 cl, 1 tbl, 3 dwg