1. Scope

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 acccompanies Specification B 439 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 and the technical literature.

1.7 With the exception of density values for which the g/cm ³ unit is the industry standard, the values stated in inch-pound units are to be regarded as standard. The SI equivalents of inch-pound units, shown in parenthesis, have been converted in accordance with IEEE/ASTM SI 10, may be approximate and are only for information.

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 and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

B243 Terminology of Powder Metallurgy

B439 Specification for Iron-Base Powder Metallurgy (PM) Bearings (Oil-Impregnated)

B939 Test Method for Radial Crushing Strength, K, of Powder Metallurgy (PM) Bearings and Structural Materials

B946 Test Method for Surface Finish of Powder Metallurgy (PM) Products

B962 Test Methods for Density of Compacted or Sintered Powder Metallurgy (PM) Products Using Archimedes Principle

B963 Test Methods for Oil Content, Oil-Impregnation Efficiency, and Interconnected Porosity of Sintered Powder Metallurgy (PM) Products Using Archimedes Principle

B966 Test Method for Permeability of Powder Metallurgy (PM) Bearings Using Nitrogen Gas

B970 Test Method for Cleanliness of Powder Metallurgy (PM) Bearings and Structural Parts

E9 Test Methods of Compression Testing of Metallic Materials at Room Temperature

E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

E1019 Test Methods for Determination of Carbon, Sulfur, Nitrogen, and Oxygen in Steel, Iron, Nickel, and Cobalt Alloys by Various Combustion and Fusion Techniques

Government Standards

ISO Standard

MPIF Standard

Keywords

bearing breaking load; bronze bearings; impregnated density; interconnected porosity; oil content; oil-impregnated bearings; open porosity; porous metallic bearings; radial crushing strength; self-lubricating bearings; PM bearings; PV Factor; PV Limit;

ICS Code

ICS Number Code 21.100.01 (Bearings in general)

DOI: 10.1520/B0438-08

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