1.1 本试验方法包括测定新的或使用过的电绝缘油中2,6-二叔丁基对甲酚（DBPC）和2,6-二叔丁基苯酚（DBP）的重量百分比，浓度高达0.5 % 通过在红外光谱的指定波长下测量其吸光度。 1.2 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户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。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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》中确立的国际公认标准化原则制定的。 ====意义和用途====== 3.1 新电气绝缘油中2,6-二叔丁基对甲酚和2,6-二叔丁基苯酚的定量测定测量了添加到油中以防氧化的该材料的量。在废油中，它测量氧化降低其浓度后剩余的量。该测试也适用于制造控制和规范验收。 3.2 当获得被这些化合物之一抑制的电绝缘油的红外光谱时，光谱在几个波长（或波数）的吸光度增加。2,6二叔丁基对甲酚在2.72μm（3650 cm）处的吸光度显著增加 −1. )和11.63μm（860 cm −1. ). 2,6二段式- 丁基苯酚在2.72μm（3650 cm）处的吸光度显著增加 −1. )和13.42μm（745 cm −1. ). 3.3 当在高度氧化的油以外的油上进行此测试或使用双光束分光光度计时，可以方便地获得2.5μm（4000 cm）之间的光谱 −1. )和2.9μm（3450 cm −1. )因为仪器对水分的存在进行了补偿，并且谱带不受分子间力（关联）的影响。然而，当测试高度氧化的油或使用单光束仪器时，如果在10.90μm（918 cm）之间进行扫描，可能会获得更好的结果 −1. )和14.00μm（714 cm −1. ). 3.4 11.63μm（860 cm）处吸收增加 −1. )或13.42μm（745 cm −1. )或者两者都可以将抑制剂识别为2,6-二叔丁基对甲酚或2,6- 二叔丁基苯酚( 注1 ). 注1: 745 cm处的吸光度 −1. 对于2,6-二叔丁基苯酚和860 cm −1. 对于同等浓度的2,6-二叔丁基对甲酚，其比例约为2.6:1。

1.1 This test method covers the determination of the weight percent of 2,6-ditertiary-butyl paracresol (DBPC) and 2,6-ditertiary-butyl phenol (DBP) in new or used electrical insulating oil in concentrations up to 0.5 % by measuring its absorbance at the specified wavelengths in the infrared spectrum. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 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. 1.4 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 ====== 3.1 The quantitative determination of 2,6-ditertiary-butyl paracresol and 2,6-ditertiary-butyl phenol in a new electrical insulating oil measures the amount of this material that has been added to the oil as protection against oxidation. In a used oil it measures the amount remaining after oxidation has reduced its concentration. The test is also suitable for manufacturing control and specification acceptance. 3.2 When an infrared spectrum is obtained of an electrical insulating oil inhibited with either of these compounds there is an increase in absorbance of the spectrum at several wavelengths (or wavenumbers). 2,6 ditertiary-butyl paracresol produces pronounced increases in absorbance at 2.72 μm (3650 cm −1 ), and 11.63 μm (860 cm −1 ). 2,6 ditertiary-butyl phenol produces pronounced increases in absorbance at 2.72 μm (3650 cm −1 ) and 13.42 μm (745 cm −1 ). 3.3 When making this test on other than a highly oxidized oil or when using a double-beam spectrophotometer, it has been found convenient to obtain the spectrum between 2.5 μm (4000 cm −1 ) and 2.9 μm (3450 cm −1 ) because the instrument is compensated for the presence of moisture and the band is not influenced by intermolecular forces (associations). However, when testing a highly oxidized oil or when using a single-beam instrument better results may be obtained if the scan is made between 10.90 μm (918 cm −1 ) and 14.00 μm (714 cm −1 ). 3.4 Increased absorption at 11.63 μm (860 cm −1 ) or 13.42 μm (745 cm −1 ) or both, will identify the inhibitor as 2,6-ditertiary-butyl paracresol or 2,6-ditertiary-butyl phenol respectively ( Note 1 ). Note 1: The absorbance at 745 cm −1 for 2,6-ditertiary-butyl phenol and at 860 cm −1 for 2,6-ditertiary-butyl paracresol for equal concentrations will be in the approximate ratio of 2.6 to 1.