EXPLANATION
Costs associated with damages due to engine and machine wear can be very significant. Thus, diagnostic methods for determining the condition of an engine or other equipment in service are important. This test method, which is a diagnostic method that indicates the condition of oil-wetted components in engines, represents the only test method for the quantitative determination of metals in used oils. This test method covers the determination of additive elements, wear metals, and contaminants in used lubricating oils by inductively coupled plasma atomic emission spectrometry (ICPAES). It can also be used for unused oils to provide more complete elemental composition data than Test Methods ASTM D4628, ASTM D4927, or ASTM D4951.
TEST SUMMARY
A weighed portion of a thoroughly homogenized used oil is diluted 10-fold by weight with mixed xylenes or other suitable solvent. Standards are prepared in the same manner. An optional internal standard can be added to the solutions to compensate for variations in sample introduction efficiency. The solutions are introduced to the ICP instrument by free aspiration or an optional peristaltic pump. By comparing emission intensities of elements in the specimen with emission intensities measured with the standards, the concentrations of elements in the specimen are calculable.
TEST PRECISION
