HOMOGENITY AND MISCIBILITY OF ENGINE OILS: ASTM D6922
EXPLANATION
It is important that engine oils from different manufacturers be homogenous and miscible with each other, because operators of automotive engines often do not have prior knowledge of the manufacturer of the oil that is currently used in their application, and engine failure can occur if oils are combined that do not stay homogenous and function properly.
This test method covers the determination if an automotive engine oil is homogenous and will remain so, and if it is miscible with certain standard reference oils after being submitted to a prescribed cycle of temperature changes. This test method is very similar to the homogeneity and miscibility test described in FED-STD-791/3470.1.
TEST SUMMARY
Visual color determinations and observations are made on an undiluted test oil specimen, along with six blends of the same test oil that have been combined with specific reference oils. The pour point is then determined for the undiluted test oil specimen and the six blends. They are then allowed to warm to room temperature. Color determinations and observations are again made on the undiluted test oil specimen and six blends. They are then heated to 232° C, then allowed to cool to room temperature, and then stored at their pour point temperature for 18 to 24 h. All samples are then allowed to thaw and a series of color determinations and observations are made as they reach room temperature. All data are recorded on a report form.
TEST PRECISION
No information is presented about either the precision or the bias of this method since the test results are nonquantitative.
