1.1 本规程涵盖了规范中定义的液压流体混合物的兼容性 D6158 、DIN 51524、ISO 11158和ISO 15380。 1.2 本规程可用于评估新（未使用）润滑剂的兼容性，或评估新（更换）润滑剂与系统中在用（原始）润滑剂的组合效果。 1.3 为了使用该方法评估主要相容性，更换液必须通过ISO 13357-1第二阶段可过滤性测试。原始流体无需通过ISO 13357-1第一或第二阶段可过滤性测试。 1.4 使用ISO 13357-1第二阶段可过滤性测试，以2:98、10:90和50:50的比例对流体混合物进行初步测试。 1.5 当情况表明需要额外测试时，建议进行二次测试。 1.6 本规程不评估润滑剂混合物在使用过程中的耐磨特性、承载能力或机械剪切稳定性。如果要评估耐磨性（AW）、极压（EP）或剪切稳定性，可能需要对这些参数进行进一步测试。 1.7 本规程并未涵盖所有可采用的试验方法。 1.8 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。 1.9 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。 1.10 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====== 5.1 液压流体兼容性对液压设备用户来说很重要，因为不兼容流体的混合物可能会产生明显低于其成分的物质。即使在相同的基础油中，沉淀的形成也可能是加性相互作用的结果。在本实践中，将使用ISO 13357-1可过滤性测试方法确定兼容性。由于液压系统利用精细过滤来保护部件免受磨损，不相容性通常表现为过早堵塞过滤器。 5.2 鉴于此类情况，供应商建议在混合之前评估液压油的兼容性。流程图如所示 附件A1 帮助解释测试结果和液压系统转换。 5.3 虽然新的液压油可能兼容，但同一类型的在用液压油可能会降解或污染，以至于添加的新液压油可能与系统液压油不兼容。在役流体与新添加流体的相容性应根据具体情况进行评估。 5.4 同一类型的不同液体的抗氧化性和耐磨性可能差异很大，兼容性并不意味着具有同等的性能。

1.1 This practice covers the compatibility of mixtures of hydraulic fluids as defined by Specifications D6158 , DIN 51524, ISO 11158, and ISO 15380. 1.2 This practice can be used to evaluate new (unused) lubricant compatibility or the effects of combining new (replacement) lubricant with in-service (original) lubricant in the system. 1.3 To evaluate primary compatibility using this method, the replacement fluid must pass the ISO 13357-1 Stage II filterability test. The original fluid is not required to pass ISO 13357-1 filterability test, Stage I or II. 1.4 Primary testing is conducted on fluid mixtures in 2:98, 10:90, and 50:50 ratios using the ISO 13357-1 Filterability Test, Stage II. 1.5 Secondary testing is suggested when circumstances indicate the need for additional testing. 1.6 This practice does not evaluate the wear prevention characteristics, load carrying capacity, or the mechanical shear stability of lubricant mixtures while in service. If anti-wear (AW), extreme pressure (EP), or shear stability are to be evaluated, further testing of these parameters may be required. 1.7 This practice does not purport to cover all test methods that could be employed. 1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.9 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. 1.10 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 Hydraulic fluid compatibility is important to hydraulic equipment users because a mixture of incompatible fluids may produce a substance that is markedly inferior to its constituents. Even in identical base stocks, the formation of a precipitate may occur as a result of additive interactions. In this practice, compatibility will be determined using ISO 13357-1 filterability test method. Since hydraulic systems utilize fine-filtration to protect components from wear, incompatibility often exhibits itself as premature filter plugging. 5.2 Because of such occurrences, suppliers recommend evaluating the compatibility of hydraulic fluids prior to mixing. A flowchart is provided in Annex A1 to aid in interpretation of the test results and hydraulic system conversion. 5.3 Although new hydraulic fluids may be compatible, in-service fluid of the same type may be degraded or contaminated to such an extent that the new fluid added may not be compatible with the system fluid. In-service fluid compatibility with new fluid additions should be evaluated on a case by case basis. 5.4 The oxidation resistance and wear protection of different fluids of the same type can vary widely, and compatibility does not imply equivalent performance.