CEC L-85-T-99 Oxidative Stability of Lubricants by High Pressure Differential Scanning Calorimetry
In diesel engines, lubricating oils coat combustion chambers to allow for ease of piston movement. If the oil oxidizes during combustion, deposits may form on pistons, rings and combustion chambers compromising engine performance. This test determines the oxidative stability of a lubricant exposed to high pressure air at an elevated temperature.
The sample is placed in a PDSC, pressurized with air (100 psi) and heated until an exotherm is observed. Reported is the temperature and oxidation induction time of the diesel engine oil.
Note: CEC L-85-T-99 vs. ASTM D6186 Both of these tests use Pressure Differential Scanning Calorimetry (PDSC) and report an oxidation induction time. ASTM D6186 is for lubricating oils in general and CEC 85-T-99 is a more specific test for oils used in diesel engines. They differ in Pressure (CEC-85-T-99 = 100 psi; D6186 = 500 psi); time of pressurization (CEC-85-T-99 = before heating; D6186 = after test temperature is reached), and pressurizing gas (CEC-85-T-99 = air; D6186 = oxygen). ASTM D6186 is a normally a more severe test.