1.1 本指南有助于选择精密滚动轴承应用的润滑脂。本指南中的建议不适用于通用轴承应用。本指南应在两个方面产生最大影响:( 1. )当为新轴承应用选择润滑脂时，以及( 2. )当由于无法再获得指定用于轴承的原始润滑脂而必须更换轴承润滑脂时。报告（见第节 5. )包含对轴承应用中常用的各种润滑脂进行的一系列测试，以比较委员会认为在选择润滑脂时最重要的润滑脂的性能。 每个测试由同一实验室进行。本指南按基础油类型列出了润滑脂的性能，即酯、全氟聚醚（PFPE）、聚α烯烃（PAO）等。这种组织是必要的，因为特定轴承应用中的操作要求可能会由于其温度稳定性、粘度指数或温度蒸汽压特性等而限制润滑脂对特定基础油类型和增稠剂的选择。本指南提供了数据，以帮助用户为已测试但不再可用的润滑脂选择替代润滑脂。 本指南还包括用于描述/讨论精密轴承和仪器轴承润滑的术语表。 1.2 本指南中介绍的润滑脂通常用于精密滚动轴承（PREB）。根据从国防部、OEM和润滑脂制造商获得的润滑脂调查，选择这些润滑脂进行测试，并根据摩擦学小组委员会F34设计的测试方案进行评估。本试验方案涵盖了精密轴承润滑脂的基本要求。这些润滑脂的性能要求非常独特。 它们取决于精密轴承的性能预期，包括高速、低噪音、延长寿命以及轴承润滑系统不会污染周围部件。为了提高测试数据的可靠性，所有测试均由一个国防部实验室和三个独立测试实验室进行。除基础油粘度外，没有进口润滑脂制造商的数据。大多数测试由美国陆军坦克-汽车研究、开发和工程中心（TARDEC）和三个独立实验室进行，结果由海军研究实验室（NRL）监测。 通过避免不同实验室使用不同或甚至“相同”程序测试润滑脂时引入的一些变异性，这种测试的连续性应为比较所测试的多种润滑脂的性能奠定坚实的基础。如果遵循规定的方案，且试验由独立实验室进行，将考虑纳入其他试验数据。 1.3 该研究是国防部老化飞机更换计划的一部分，由国防后勤代理（DLA）和里士满国防供应中心（DSCR）支持。 2. 1.4 以英寸-磅单位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 本标准并不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建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 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====== 4.1 本指南的目的是报告精密滚动元件轴承（PREB）的测试、讨论和比较其性能，并为其提供润滑脂选择指南。就本指南而言，PREB旨在包括环形轴承工程师委员会（ABEC）5质量及以上的轴承。本指南将其范围限制在PREB中使用的润滑脂。 4.2 从20世纪40年代初到90年代中期，PREB中使用的润滑脂数量急剧增加。在这一时期开始时，石油产品是唯一广泛可用的基础库存。 后来，合成基础油出现了。它们包括合成烃、酯、硅酮、多烷基化环戊烷（MAC）和氟化材料，包括全氟醚和氟硅酮。广泛的润滑剂选择导致在PREB应用中使用大量不同的润滑剂。美国国防部作为许多PREB的用户，已经看到支持这些物品的采购和分销所需的后勤工作显著增加。此外，随着时间的推移，由于先进的轴承技术/要求，某些PREB中使用的一些润滑脂不再可用或需要改进性能。 这意味着必须找到替代润滑脂，特别是在延长国防部资产使用寿命的时代，以及由此产生的对替代零件来源的未计划需求。 4.3 本研究的主要目标之一是对PREB中使用的润滑脂进行广泛的测试，并对其进行一系列全面的测试，以便对其性能进行比较，并在必要时确定潜在的替代润滑脂。本研究还旨在为未来PREB应用选择润滑脂提供设计指南。 本指南代表了该社区的许多成员的集体努力，这些成员包括轴承制造商、原始设备制造商（OEM）、润滑脂制造商和供应商、采购专家、国防部和国防部内外最终用户的质量保证代表（QAR）。 4.4 强烈建议在更换PREB中的润滑脂之前，应清除轴承上的所有现有润滑脂。不相容润滑脂之间可能发生反应，导致性能严重下降。当用户使用多种类型的润滑脂时，必须制定维护规程，以避免润滑脂意外混合。 此外，在润滑轴承之前，应清除所有专门用于延长PREBs（防腐剂）储存寿命的液体。可能发生会使润滑脂降解的反应。 4.5 基础油、增稠剂和添加剂决定了润滑脂的性能。许多基础油的性能可以在之前的研究中找到（指南 F2161 ). 本研究包括对弹流润滑理论的讨论。

1.1 This guide is a tool to aid in the choice of lubricating grease for precision rolling element bearing applications. The recommendations in this guide are not intended for general purpose bearing applications There are two areas where this guide should have the greatest impact: ( 1 ) when lubricating grease is being chosen for a new bearing application and ( 2 ) when grease for a bearing has to be replaced because the original grease specified for the bearing can no longer be obtained. The Report (see Section 5 ) contains a series of tests on a wide variety of greases commonly used in bearing applications to allow comparisons of those properties of the grease that the committee thought to be most important when making a choice of lubricating grease. Each test was performed by the same laboratory. This guide contains a listing of the properties of greases by base oil type, that is, ester, perfluoropolyether (PFPE), polyalphaolefin (PAO), and so forth. This organization is necessary since the operational requirements in a particular bearing application may limit the choice of grease to a particular base oil type and thickener due to its temperature stability, viscosity index or temperature-vapor pressure characteristics, etc. The guide provides data to assist the user in selecting replacement greases for those greases tested that are no longer available. The guide also includes a glossary of terms used in describing/discussing the lubrication of precision and instrument bearings. 1.2 The lubricating greases presented in this guide are commonly used in precision rolling element bearings (PREB). These greases were selected for the testing based on the grease survey obtained from DoD, OEM and grease manufactures and evaluated according to the test protocol that was designed by Subcommittee F34 on Tribology. This test protocol covers the essential requirements identified for precision bearing greases. The performance requirements of these greases are very unique. They are dictated by the performance expectations of precision bearings including high speed, low noise, extended life, and no contamination of surrounding components by the bearing’s lubricant system. To increase the reliability of test data, all tests were performed by a DoD laboratory and three independent testing laboratories. There were no grease manufacturer’s data imported except for base oil viscosity. Most of tests were performed by U.S. Army Tank–Automotive Research, Development and Engineering Center (TARDEC) and three independent laboratories, and the results were monitored by the Naval Research Laboratory (NRL). This continuity of testing should form a solid basis for comparing the properties of the multitude of lubricating greases tested by avoiding some of the variability introduced when greases are tested by different laboratories using different or even the “same” procedures. Additional test data will be considered for inclusion, provided the defined protocol is followed and the tests are performed by independent laboratories. 1.3 This study was a part of DoD Aging Aircraft Replacement Program and supported by Defense Logistic Agent (DLA) and Defense Supply Center Richmond (DSCR). 2 1.4 The values stated in inch-pound 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 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 ====== 4.1 The purpose of this guide is to report on the testing of, to discuss and compare the properties of, and to provide guidelines for the choice of lubricating greases for precision rolling element bearings (PREB). The PREB are, for the purposes of this guide, meant to include bearings of Annular Bearing Engineer's Committee (ABEC) 5 quality and above. This guide limits its scope to lubricating greases used in PREB. 4.2 The number of lubricating greases used in PREB increased dramatically from the early 1940s to the mid 1990s. In the beginning of this period, petroleum products were the only widely available base stocks. Later, synthetic base oils became available. They included synthetic hydrocarbons, esters, silicones, multiply alkylated cyclopentanes (MAC) and fluorinated materials, including perfluorinated ethers and the fluorosilicones. This broad spectrum of lubricant choices has led to the use of a large number of different lubricants in PREB applications. The U.S. Department of Defense, as a user of many PREB, has seen a significant increase in the logistics effort required to support the procurement and distribution of these items. In addition, as time has passed, some of the greases used in certain PREB are no longer available or require improved performances due to advanced bearing technology/requirements. This implies that replacement lubricating greases must be found, especially in this era of extending the lifetime of DoD assets, with the consequent and unprojected demand for sources of replacement parts. 4.3 One of the primary goals of this study was to take a broad spectrum of the lubricating greases used in PREB and do a comprehensive series of tests on them in order that their properties could be compared and, if necessary, potential replacement greases be identified. This study is also meant to be a design guide for choosing lubricating greases for future PREB applications. This guide represents a collective effort of many members of this community who span the spectrum from bearing manufacturers, original equipment manufactures (OEMs), grease manufacturers and suppliers, procurement specialists, and quality assurance representatives (QARs) from DoD and end users both inside and outside DoD. 4.4 It is strongly recommend that, prior to replacing a grease in a PREB, all of the existing grease should be removed from the bearing. Reactions may occur between incompatible greases resulting in severely degraded performance. When users have more than one type of grease in service, maintenance practices must be in place to avoid accidental mixing of greases. In addition, all fluids used specifically to prolong storage life of PREBs (preservatives) should be removed prior to lubricating the bearings. Reactions may occur which would degrade the grease. 4.5 The base oils, thickeners, and additives dictates grease performances. The properties of many base oils can be found in the previous study (Guide F2161 ). This study included a discussion of elastohydrodynamic lubrication theory.