ASTM E1858 Determining Oxidation Induction Time of Hydrocarbons by Differential Scanning Calorimetry
Lubricants may react with oxygen to produce acids, varnish, sludge and viscosity changes. The rate of oxidation increases with temperature and in the presence of water, acids and metals. This test measures the relative oxidative stability of lubricants, fats or oils.
The sample is placed in the PDSC (pressure differential scanning calorimeter), pressurized with oxygen and heated to the test temperature. The time it takes for an oxidation exotherm to start is determined and reported. This method has two options: Test method A is run at atmospheric pressure with an oxygen purge. It is typically run at 195°C. Test Method B is run at 500 psi oxygen and 175°C.
Related tests: Petro-Lube offers a variety of differential scanning calorimetry tests. For the specific heat consider ASTM E1269. For thermal conductivity consider PLTL-73. For thermal characteristics including phase changes consider PLTL-108. For oxidation onset temperature consider ASTM E2009. For oxidation onset times in an oxygen atmosphere consider ASTM E1858 for ambient pressure, and ASTM D5483 (grease) or ASTM D6186 (oil) for 500 psi. Consider CEC L-85-T-99 for oxidative stability under an air atmosphere. For glass transition temperatures, consider ASTM E1356.
Sample size: 10 g
- ASTM D5483 – Oxidation Stability of Greases by PDSC – 1 run for screening. $22.00/hr charge after 2 hrs.
- ASTM D6186 – Oxidation Stability of Oils by PDSC
- ASTM E1269 – Specific Heat by DSC (multi temps one charge)
- ASTM E1858 – Oxidation Induction Time of Hydrocarbons by DSC
- ASTM E2009 – Oxidation Onset Temperature by Differential Scanning Calorimetry (DSC)
- CEC L-85-T-99 – Oxidative Stability of Lubricants by PDSC (Pressure Differential Scanning Calorimetry)
- PLTL-73 – Thermal Conductivity by DSC- (charge per temp) specify temperature. 38°C to 100°C typical is
- PLTL-108 – DSC Thermogram
- ASTM E1356 – Glass Transition Temperature by Differential Scanning Calorimetry (DSC)