METHOD FOR EVALUATION OF TENDENCY OF LUBRICATING OILS TO FORMATION OF HIGH TEMPERATURE DEPOSITS Russian patent published in 2016 - IPC G01N33/28 G01N5/00 

FIELD: physics; chemistry.

SUBSTANCE: invention relates to investigation of thermal-oxidative degradation of lubricating oil and formation of high temperature deposits on surfaces of heat-loaded parts of engines. For this purpose, gravimetric method of determining weight of separate cup-evaporator without tested lubricating oil $$M_i^U$$ and weight of separate cup-evaporator with tested lubricating oil $$M_i^M.$$ Test specimen is kept at temperature (T) and during time (τ), sufficient for formation of high temperature deposits. After that, weight of lubricating oil is determined, subjected to evaporation $$M_i^I.$$ Then sample is washed with isooctane, dried and weight of cup-evaporator is determined with produced lacquer deposits $$M_i^L.$$ After drying of formed high temperature deposits total weight of insoluble in isooctane sediment (X) extracted during washing cups-evaporators is determined. Preserved working fraction of tested lubricating oil is calculated by presented formula.

EFFECT: invention enables more reliable assessment of lubricating oils by degree of their effect on operational reliability of engines when estimating depth of thermal-oxidative degradation of lubricating oil in general.

1 cl, 1 dwg, 1 tbl