The ASTM D 5800 test method measures the evaporation loss of lubricating oils, particularly engine oils, by heating a sample to 250 °C and drawing a constant flow of air through it. The loss in mass of the oil is then determined. The results are reported as a percentage of total loss.
Here are some details about the ASTM D 5800 test method:
- Sample placement – A measured amount of the sample is placed in an evaporation crucible or reaction flask.
- Heating – The sample is heated for 60 minutes.
- Temperature measurement – The specimen temperature measuring device should have an accuracy of 0.5 °C or better and a resolution of 0.1 °C or better.
- Evaporation loss calculation – The evaporation loss of the sample is determined by the difference in mass of the sample before and after heating.
- Precision – Inter laboratory tests have shown that the four procedures in the test method yield statistically equivalent precision.
- Before the first test, the unit should be turned on with the heat and vacuum pump for 15–30 minutes