1.1本规程可用于通过与基本物理性能的相关性来确定矿物绝缘油的碳型成分。出于常规分析目的，它消除了复杂的部分分离和纯化程序的必要性。本规程适用于平均分子量为200至600以上、芳香族碳原子为0至50的油。 1.2碳类型组成表示为芳香碳百分比、环烷碳百分比和石蜡碳百分比。 如果粘度-重力常数（VGC）和折射率截距同时存在，则可以从图1的相关图中获得这些值( r 一、 )已知的油的数量。粘度、密度和相对密度（比重）以及折射率是使用本试验方法所需的唯一实验数据。 1.3本规程有助于确定电力变压器和输电电缆中常用类型的电绝缘油的碳型成分。 它主要用于抑制或不抑制的新油。 1.4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。 1.5 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和健康实践，并确定监管限制的适用性。 图1确定百分比的相关图 C A. , % C N ，和% C P ====意义和用途====== 本规程的主要目的是表征油的碳型成分。它还适用于观察各种精炼过程（如加氢处理、溶剂萃取等）对油组成的影响。它在将油的化学性质与已证明与油成分有关的其他现象联系起来方面有二次应用。 本规程获得的结果与试验方法D 3238获得的结果相似，但不完全相同 . 文献中讨论了两者之间的关系以及推导图1时使用的方程。 尽管这种做法倾向于给出一致的结果，但可能无法与直接测量测试方法（如测试方法D 2007）进行比较 .

1.1 This practice may be used to determine the carbon-type composition of mineral insulating oils by correlation with basic physical properties. For routine analytical purposes it eliminates the necessity for complex fractional separation and purification procedures. The practice is applicable to oils having average molecular weights from 200 to above 600, and 0 to 50 aromatic carbon atoms. 1.2 Carbon-type composition is expressed as percentage of aromatic carbons, percentage of naphthenic carbons, and percentage of paraffinic carbons. These values can be obtained from the correlation chart, Fig. 1, if both the viscosity-gravity constant (VGC) and refractivity intercept ( r i ) of the oil are known. Viscosity, density and relative density (specific gravity), and refractive index are the only experimental data required for use of this test method. 1.3 This practice is useful for determining the carbon-type composition of electrical insulating oils of the types commonly used in electric power transformers and transmission cables. It is primarily intended for use with new oils, either inhibited or uninhibited. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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 and health practices and determine the applicability of regulatory limitations prior to use. FIG. 1 Correlation Chart for Determining % C A , % C N , and % C P ====== Significance And Use ====== The primary purpose of this practice is to characterize the carbon-type composition of an oil. It is also applicable in observing the effect on oil constitution, of various refining processes such as hydrotreating, solvent extraction, and so forth. It has secondary application in relating the chemical nature of an oil to other phenomena that have been demonstrated to be related to oil composition. Results obtained by this practice are similar to, but not identical with, results obtained from Test Method D 3238 . The relationship between the two and the equations used in deriving Fig. 1 are discussed in the literature. Although this practice tends to give consistent results, it may not compare with direct measurement test methods such as Test Method D 2007 .