Active Standard ASTM D7751 | Developed by Subcommittee: D02.03
Book of Standards Volume: 05.04
Historical (view previous versions of standard)
Significance and Use
5.1 Lubricating oils are formulated with organo-metallic additives, which act, for example, as detergents, antioxidants, antifoaming, or antiwear agents, or a combination thereof. Some of these additives contain one or more of the following elements: magnesium, phosphorus, sulfur, chlorine, calcium, zinc, and molybdenum. This test method provides a means of determining the concentrations of these elements, which in turn provides an indication of the additive content of these oils.
5.4 If this test method is applied to lubricating oils with matrices significantly different from the calibration materials specified in this test method, the cautions and recommendations in Section 6 should be observed when interpreting the results.
1.1 This test method covers the quantitative determination of additive elements in unused lubricating oils and additive packages, as shown in Table 1. The pooled limit of quantitation of this test method as obtained by statistical analysis of interlaboratory test results is 0.02% for magnesium, 0.003 % for phosphorus, 0.002 % for sulfur, 0.001 % for chlorine, 0.003 % for calcium, 0.001 % for zinc, and 0.002 % for molybdenum.
1.2 Additive packages require dilution with a contamination free diluent (base oil) prior to analysis. The dilution factor has to be calculated from the expected concentrations to bring the concentrations for all elements into the ranges listed in Table 1.
1.3 Some lubrication oils will contain higher concentrations than the maximum concentrations listed in Table 1. These samples require dilution with a contamination free diluent (base oil) prior to analysis. The dilution factor has to be calculated from the expected concentrations to bring the concentrations for all elements into the ranges listed in Table 1.
1.4 This test method is limited to the use of energy dispersive X-ray fluorescence (EDXRF) spectrometers employing an X-ray tube for excitation in conjunction with the ability to separate the signals of adjacent elements by using a high resolution semiconductor detector.
1.6.1 The preferred concentration units are mg/kg or mass %.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4177 Practice for Automatic Sampling of Petroleum and Petroleum Products
D6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measurement System Performance
D6300 Practice for Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products and Lubricants
D6792 Practice for Quality System in Petroleum Products and Lubricants Testing Laboratories
D7343 Practice for Optimization, Sample Handling, Calibration, and Validation of X-ray Fluorescence Spectrometry Methods for Elemental Analysis of Petroleum Products and Lubricants
E1621 Guide for X-Ray Emission Spectrometric Analysis
ISO StandardsISO 4259 Determination and application of precision data in relation to methods of test
ICS Number Code 75.100 (Lubricants, industrial oils and related products)