石油及相关产品.防腐蚀矿物油和液体老化性的测定.透平油稳定性(TOST)试验.第3部分:合成液压液的无水规程

[中文适用范围]： ISO 4263 的这一部分规定了测定 HFDU、HEES、HEPG 和 HETG 类合成液压油老化行为的方法，例如 ISO 12922[1] 中定义的温度，并跟踪流体的降解情况通过酸值的变化。 用于液压和其他应用的指定类别的耐火液体的其他部分。 注：可能出现流体变质的其他迹象，例如不溶性污泥的形成、催化剂线圈腐蚀或粘度变化，这表明流体发生氧化，但不会反映在计算的氧化寿命中。 这些事件与现场服务的相关性正在调查中。 该测试方法可用于比较不易被水污染的流体的氧化稳定性。 然而，由于单个现场服务应用程序数量众多，该测试结果与实际服务性能之间的相关性可能会有很大差异，最好根据经验来判断。 由于无法获得实验室间数据，因此合成液压油的这种测试方法的精度尚不清楚。 只要这些数据不可用，该方法可能不适合在规范中使用或在结果有争议的情况下使用。 [外文原描述]： ISO 4263-3:2015 specifies a method for the determination of the ageing behaviour of synthetic hydraulic fluids of categories HFDU, HEES, HEPG and HETG as defined, for example, in ISO 12922[1] and ISO 15380[2]. The ageing is accelerated by the presence of oxygen and metal catalysts at elevated temperature, and the degradation of the fluid is followed by changes in acid number. Other parts of ISO 4263 specify similar procedures for the determination of ageing behaviour of mineral oils and specified categories of fire-resistant fluids used in hydraulic and other applications. NOTE Other signs of fluid deterioration, such as the formation of insoluble sludge, catalyst coil corrosion or change in viscosity, can occur which indicate oxidation of the fluid, but are not reflected in the calculated oxidation lifetime. The correlation of these occurrences with field service is under investigation. This test method may be used to compare the oxidation stability of fluids that are not prone to contamination with water. However, because of the large number of individual field-service applications, the correlation between the results of this test and actual service performance can vary markedly, and is best judged on experience. The precision of this test method for synthetic hydraulic fluids is not known because interlaboratory data are not available. This method might not be suitable for use in specifications or in the event of disputed results as long as these data are not available.