1.1 本试验方法评估汽油汽车发动机机油的氧化稳定性。此测试在160下运行 在部分模拟汽油发动机中机油可能受到的条件时，°C，利用高压氧气加压反应器以及金属催化剂包、燃料催化剂和水。本试验方法可用于粘度在4 毫米 2. /s（cSt）至21 毫米 2. /100时的s（cSt） °C，包括再精炼油。 1.2 该试验方法不能代替已建立的发动机试验中的发动机机油试验，如IIID序列。 1.3 以国际单位制表示的数值应视为标准。 本标准中不包括其他计量单位。 1.3.1 例外-- 压力单位以psig为单位，尺寸以英寸为单位 附件A1 ，因为这些是行业公认的标准，并且设备是根据所示的数字建造的。 1.4 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 有关具体的警告声明，请参阅章节 7. 和 8. 。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ===意义和用途====== 5.1 本试验方法用于评估含有添加剂的润滑基础油在存在类似于汽油发动机中发现的化学物质的情况下的氧化稳定性。已发现一些ASTM参考油的测试结果与375 % 粘度增加。 5. 该测试不能代替发动机测试，发动机测试测量润滑剂的磨损、氧化稳定性、挥发性和沉积物控制特性。正确解释，该测试可以提供模拟发动机化学条件下润滑剂氧化稳定性的输入。 5.2 该测试方法旨在用作润滑基础油制造的台架筛选测试和质量控制工具，尤其是用于- 精制润滑基础油。该试验方法可用于逐批再精炼油氧化稳定性的质量控制。 5.3 该试验方法可用于在发动机试验前筛选配方油。在类似的添加剂化学和基础油类型中，本测试中的机油排名似乎可以预测发动机测试中的排名。当比较添加剂化学性质或基础油类型完全不同的机油时，氧化稳定性结果可能无法反映实际的发动机测试结果。 5.4 其他氧化稳定性测试方法已经证明可溶性金属催化剂的供应非常不一致，并且它们对测试结果有显著影响。 因此，为了进行试验比较，应使用相同来源和相同批次的金属环烷酸盐。 注2: 还建议在试验比较中不要使用不同批次的燃料组分，这是一种良好的研究实践。

1.1 This test method evaluates the oxidation stability of engine oils for gasoline automotive engines. This test, run at 160 °C, utilizes a high pressure reactor pressurized with oxygen along with a metal catalyst package, a fuel catalyst, and water in a partial simulation of the conditions to which an oil may be subjected in a gasoline combustion engine. This test method can be used for engine oils with viscosity in the range from 4 mm 2 /s (cSt) to 21 mm 2 /s (cSt) at 100 °C, including re-refined oils. 1.2 This test method is not a substitute for the engine testing of an engine oil in established engine tests, such as Sequence IIID. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3.1 Exception— Pressure units are provided in psig, and dimensions are provided in inches in Annex A1 , because these are the industry accepted standard and the apparatus is built according to the figures shown. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see Sections 7 and 8 . 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 This test method is used to evaluate oxidation stability of lubricating base oils with additives in the presence of chemistries similar to those found in gasoline engine service. Test results on some ASTM reference oils have been found to correlate with sequence IIID engine test results in hours for a 375 % viscosity increase. 5 The test does not constitute a substitute for engine testing, which measures wear, oxidation stability, volatility, and deposit control characteristics of lubricants. Properly interpreted, the test may provide input on the oxidation stability of lubricants under simulated engine chemistry. 5.2 This test method is intended to be used as a bench screening test and quality control tool for lubricating base oil manufacturing, especially for re-refined lubricating base oils. This test method is useful for quality control of oxidation stability of re-refined oils from batch to batch. 5.3 This test method is useful for screening formulated oils prior to engine tests. Within similar additive chemistry and base oil types, the ranking of oils in this test appears to be predictive of ranking in engine tests. When oils having completely different additive chemistry or base oil type are compared, oxidation stability results may not reflect the actual engine test result. 5.4 Other oxidation stability test methods have demonstrated that soluble metal catalyst supplies are very inconsistent and they have significant effects on the test results. Thus, for test comparisons, the same source and same batch of metal naphthenates shall be used. Note 2: It is also recommended as a good research practice not to use different batches of the fuel component in test comparisons.