PROCESS EVALUATING SEDIMENTATION STABILITY OF MOTOR OILS Russian patent published in 1999 - IPC

FIELD: testing of lubricating oils in petroleum refining and other branches of industry while predicting storage life of motor oils. SUBSTANCE: alkaline number and kinematic viscosity are taken as informative indices. Centrifugation is carried out in the course of 8 (±) h with separation factor of 20000±100 units. After it specimens are taken out of all test tubes. Specimens are mixed, alkaline number and kinematic viscosity of this mixture is found. Sedimentation stability is evaluated by generalized index determined as square root from product of relative rates of change of alkaline number and kinematic viscosity during centrifugation time. EFFECT: timely and authentic evaluation of sedimentation stability of motor oils and low cost of process. 5 tbl