1.1 本规范涵盖多孔金属套筒、法兰、止推轴承和球形青铜底座轴承，这些轴承由使用粉末冶金（PM）技术的混合金属粉末制成，然后浸渍油以提供运行润滑。 1.2 其中包括青铜基粉末冶金材料的化学、物理和机械要求规范，这些材料是专门为制造这些自润滑轴承而开发和标准化的。 1.3 本规范适用于购买以前由军事规范涵盖的、用于政府或军事应用的青铜底座轴承（油浸轴承）。这些仅适用于军用轴承的附加政府要求列于本规范的补充要求部分。 1.4 本规范随附规范 B439页 这涵盖了铁基粉末冶金（PM）轴承（油浸）的要求。 1.5 青铜底座轴承的典型应用列于 附录X1 . 1.6 轴承尺寸公差数据如所示 附录X2 ，而有关永磁轴承安装和运行参数的工程信息包含在 附录X3 . 有关自润滑轴承的其他有用信息，请参阅MPIF标准35、ISO 5755和技术文献。 2. 1.7 除用于确定密度的密度值和质量值外，使用克每立方厘米（g/cm 3. )克（g）单位是行业标准，以英寸-磅单位表示的数值应视为标准。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.8 以下安全隐患警告仅适用于本规范中描述的测试方法。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。 1.9 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。

1.1 This specification covers porous metallic sleeve, flange, thrust, and spherical bronze-base bearings that are produced from mixed metal powders utilizing powder metallurgy (PM) technology and then impregnated with oil to supply operating lubrication. 1.2 Included are the specifications for the chemical, physical, and mechanical requirements of those bronze-base PM materials that have been developed and standardized specifically for use in the manufacture of these self-lubricating bearings. 1.3 This specification is applicable to the purchase of bronze-base bearings (oil-impregnated) that were formerly covered by military specifications and are intended for government or military applications. Those additional government requirements that only apply to military bearings are listed in the Supplementary Requirements section of this specification. 1.4 This specification accompanies Specification B439 that covers the requirements for Iron-Base Powder Metallurgy (PM) Bearings, (Oil-Impregnated). 1.5 Typical applications for bronze-base bearings are listed in Appendix X1 . 1.6 Bearing dimensional tolerance data are shown in Appendix X2 , while engineering information regarding installation and operating parameters of PM bearings is included in Appendix X3 . Additional useful information on self-lubricating bearings can be found in MPIF Standard 35, ISO 5755 and the technical literature. 2 1.7 With the exception of the values for density and the mass used to determine density, for which the use of the gram per cubic centimetre (g/cm 3 ) and gram (g) units is the industry standard, the values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.8 The following safety hazards caveat pertains only to the test methods described in this specification. 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. 1.9 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.