1、Designation: B438 08B438 13Standard Specification forBronze-Base Powder Metallurgy (PM) Bearings (Oil-Impregnated)1This standard is issued under the fixed designation B438; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers porous metallic sleeve, flange, thrust and spherical bronze-base bearings that are produc
3、ed frommixed 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 materialsthat have been developed and standardized s
4、pecifically 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 bymilitary specifications and are intended for government or military applications. Those additional gov
5、ernment requirements thatonly apply to military bearings are listed in the Supplementary Requirements section of this specification.1.4 This specification acccompaniesaccompanies Specification B439 that covers the requirements for Iron-Base PowderMetallurgy (PM) Bearings, (Oil-Impregnated).1.5 Typic
6、al 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 andoperating parameters of PM bearings is included in Appendix X3. Additional useful information on self-lubricatin
7、g bearings canbe found in MPIF Standard 35 35, ISO 5755 and the technical literature.21.7 With the exception of density values for which the g/cm3 unit is the industry standard, the values stated in inch-pound unitsare to be regarded as standard. The SI equivalents of inch-pound units, shown in pare
8、nthesis, have been converted in accordancewith IEEE/ASTM SI 10, may be approximate and are only for information. values given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.8 The following safety hazards caveat pertains
9、 only to the test methods described in this specification. This standard does notpurport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard toestablish appropriate safety and health practices and determine the applicability o
10、f regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3B243 Terminology of Powder MetallurgyB328 Test Method for Density, Oil Content, and Interconnected Porosity of Sintered Metal Structural Parts and Oil-ImpregnatedBearings (Withdrawn 2009)4B439 Specification for Iron-Bas
11、e Powder Metallurgy (PM) Bearings (Oil-Impregnated)B939 Test Method for Radial Crushing Strength, K, of Powder Metallurgy (PM) Bearings and Structural MaterialsB946 Test Method for Surface Finish of Powder Metallurgy (PM) ProductsB962 Test Methods for Density of Compacted or Sintered Powder Metallur
12、gy (PM) Products Using Archimedes PrincipleB963 Test Methods for Oil Content, Oil-Impregnation Efficiency, and Interconnected Porosity of Sintered Powder Metallurgy(PM) Products Using Archimedes PrincipleB966 Test Method for Permeability of Powder Metallurgy (PM) Bearings Using Nitrogen Gas1 This sp
13、ecification is under the jurisdiction of ASTM Committee B09 on Metal Powders and Metal Powder Products and is the direct responsibility of SubcommitteeB09.04 on Bearings.Current edition approved June 1, 2008April 1, 2013. Published July 2008May 2013. Originally approved in 1966. Last previous editio
14、n approved in 20052008 asB438/B438M 05.B438 08. DOI: 10.1520/B0438-08.10.1520/B0438-13.2 Machine Design Magazine, Vol 54, #14, June 17, 1982, pp. 130-142. Machine Design Magazine, Vol 54, #14, June 17, 1982, pp. 130-142.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactA
15、STM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been ma
16、de to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A
17、Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1B970 Test Method for Cleanliness of Powder Metallurgy (PM) Bearings and Structural PartsE9 Test Methods of Compression Testi
18、ng of Metallic Materials at Room TemperatureE29 Practice for Using Significant Digits in Test Data to Determine Conformance with SpecificationsE1019 Test Methods for Determination of Carbon, Sulfur, Nitrogen, and Oxygen in Steel, Iron, Nickel, and Cobalt Alloys byVarious Combustion and Fusion Techni
19、ques2.2 MPIF Standard:MPIF Standard 35 Materials Standards for PM Self-Lubricating Bearings42.3 IEEE/ASTM Standard:SI 10 American National Standard for Use of the International System of Units (SI): The Modernized Metric System32.3 ISO Standard:5ISO 2795 Plain Bearings Made from Sintered MetalDimens
20、ionsMaterialDimensions and TolerancesISO 5755 Sintered Metal Materials - Specifications2.4 Government Standards:MIL-PRF-6085 Lubricating Oil: Instrument, Aircraft, Low Volatility6QPL-6085 Lubricating Oil:Oil Instrument, Aircraft, Low Volatility6MIL-PRF-17331 Lubrication Oil, Steam Turbine and Gear,
21、Moderate Service6QPL-17331 Lubricating Oil, Steam Turbine and Gear, Moderate Service6MIL-B-5687 Bearings, Sleeve, Washers, Thrust, Sintered, Metal Powder, Oil-Impregnated, General Specification For6MS17795 Bearing, Sleeve, Plain, Sintered Bronze, Oil-Impregnated6MS17796 Bearing, Sleeve, Flanged, Sin
22、tered Bronze, Oil-Impregnated6MS21783 Bearing, Washer, Thrust, Sintered Bronze, Oil-Impregnated63. Terminology3.1 DefinitionsThe definitions of the terms used in this specification are found in Terminology B243. Additional descriptiveinformation is available in the Related Materials section of Volum
23、e 02.05 of the Annual Book of ASTM StandardsStandards. .4. Classification4.1 This specification uses the established three-part alphanumeric PM Material Designation Code to identify the nonferrousmaterials used for self-lubricating PM bearings. The complete explanation of this classification system
24、is presented in Annex A1.4.2 The following standard oil-impregnated bronze-base bearing material compositions are contained in this specification:4.2.1 Prefix CTBronze: CTBronze (Low Graphite):CT-1000-K19Bronze with 24 % oilCT-1000-K26Bronze with 19 % oilCT-1000-K37Bronze with 12 % oilCT-1000-K40Bro
25、nze with 9 % oilCT-1000-K19CT-1000-K26CT-1000-K37CT-1000-K404.2.2 Prefix CTGBronze-Graphite : (Medium Graphite):CTG-1001-K17Bronze, 1 % graphite with 22 % oilCTG-1001-K23Bronze, 1 % graphite with 17 % oilCTG-1001-K30Bronze, 1 % graphite with 9 % oilCTG-1001-K34Bronze, 1 % graphite with 7 % oilCTG-10
26、01-K17CTG-1001-K23CTG-1001-K30CTG-1001-K344.2.3 Prefix CTGBronze-High Graphite: CTGBronze (High Graphite):CTG-1004-K10Bronze, 4 % graphite with 11 % oilCTG-1004-K15Bronze, 4 % graphite with a trace or up to 8 % oil4 The last approved version of this historical standard is referenced on www.astm.org.
27、4 Available from MPIF, Metal Powder Industries Federation (MPIF), 105 College RoadRd. East, Princeton, NJ 08540, telephone (609) 452-7700.08540-6692,http:/www.mpif.org.5 ISO standards are available from the American National Standards Institute (ANSI), 16 West 42nd Street, 25 W. 43rd St., 4th Floor,
28、 New York, NY 10036, (212)642-4900.http:/www.ansi.org.6 Available from Standardization Documents Order Desk, Bldg DODSSP, Bldg. 4, Sec.Section D, 700 Robbins Ave,Ave., Philadelphia, PA 19111-5094. 19111-5098,http:/dodssp.daps.dla.mil. Electronic copies of military specifications may be obtained from
29、 http:/assist.daps.dla.mil/.B438 132CTG-1004-K10CTG-1004-K154.2.4 Prefix CTG-MODBronze-Lead-Graphite (Military Grade):CTG-1001-K23-MODBronze, 3 % lead, 1 % graphite with 17 % oilCTG-1001-K23-MOD4.2.5 Prefix CFTGBronze-Iron-Graphite (Diluted Bronze): CFTGBronze (Diluted):CFTG-3806-K14Bronze, 40 % iro
30、n, 0.75 % graphite with 22 % oilCFTG-3806-K22Bronze, 40 % iron, 0.75 % graphite with 17 % oilCFTG-3806-K14CFTG-3806-K225. Ordering Information5.1 Purchase orders or contracts for bronze-base, oil-impregnated bearings covered by this purchasing specification shallinclude the following information:5.1
31、.1 A copy of the bearing print showing dimensions and tolerances (Section 10),5.1.2 Reference to this ASTM Standard, including date of issue,5.1.3 Identification of bearing material by the PM Material Designation Code (section(Section 4.2),5.1.4 Request for Certification and Test Report documents, i
32、f required (Section 16),5.1.5 Type and grade of special Lubricating Oil,lubricating oil, if required (section(Section 6.2 or S2.2),5.1.6 Instructions for Special Packaging,special packaging, if required (Section 17).5.1.7 Chemical composition limits (Sections 7.2 and 13.2) if required,5.1.8 Sampling
33、 lot size (Section 12) if required,5.1.9 Testing procedure and strength requirement for the flanges of flanged oil-impregnated bearings (Section 13.4.1.2) ifrequired,5.1.10 Bearing breaking load (Section 13.4.2) if required.5.2 Those additional government requirements necessary on orders for militar
34、y bearings are prescribed in the SupplementaryRequirements section.6. Materials and Manufacture6.1 Porous Metallic Bearing:6.1.1 Sintered bronze-base bearings shall be produced by first compacting pre-alloyed bronze or elemental copper and tinpowders and any other additives appropriate for the compo
35、sition to the proper density and bearing configuration.6.1.2 The green bearings shall then be sintered in a protective atmosphere furnace for a time and temperature relationship thatwill produce the required sintered bronze-base PM material.6.1.3 After sintering, the bronze-base bearings are normall
36、y sized to achieve the density, dimensional characteristics,concentricity and surface finish required of the metallic bearing.6.2 Oil for Operating Lubrication:6.2.1 The interconnected or open porosity in the bearings shall be filled to the required volume with lubricating oil, either byan extended
37、soaking in the hot oil or preferably by a vacuum impregnation operation.6.2.2 A medium viscosity petroleum oil is normally used for most bearing applications, but extreme operating conditions suchas elevated temperatures, intermittent rotation, extremely low speeds or heavy loads may require a synth
38、etic lubricant or an oil witha different viscosity.6.2.3 Unless otherwise specified by the purchaser, a high-grade turbine oil with antifoaming additives and containing corrosionand oxidation inhibitors, having a kinematic viscosity of 280 to 500 SSU (60 10-6 to 110 10-6 m2/s), (60 to 110 cSt) at 10
39、0F(38C) 100 F (38 C) is normally used as a general purpose lubricating oil.7. Chemical Composition7.1 Chemical Composition SpecificationsEach bronze-base PM bearing material shall conform to the chemical requirementsprescribed in Table 1 when determined on a clean test sample from oil-free bearings.
40、7.2 Limits on Nonspecified ElementsBy agreement between the purchaser and the supplier, limits may be established andchemical analyses required for elements or compounds not specified in Table 1.8. Physical Properties8.1 Oil ContentFor each bearing material, the oil content of the as-received bearin
41、g shall not be less than the minimumpercentage listed in Table 1.8.2 Impregnation EffciencyA minimum of 90 %90% of the interconnected porosity in the as-received bearings shall beimpregnated with lubricating oil.B438 1338.3 Impregnated DensityThe density of the sample bearings, when fully impregnate
42、d with lubricating oil, shall meet therequirements prescribed in Table 1 for each bearing material.9. Mechanical Properties9.1 Radial Crushing StrengthThe radial crushing strength of the oil-impregnated bearing material determined on a plainsleeve bearing or a test specimen prepared from a flange or
43、 spherical bearing shall meet the minimum and maximum (if required)strength values listed in Table 1.10. Dimensions, Mass, and Permissible Variations10.1 This standard is applicable to bronze-base PM sleeve and flange bearings having a 4 to 1 maximum length to insidediameter ratio and a 24 to 1 maxi
44、mum length to wall thickness ratio.10.2 Sleeve, flange, thrust and spherical PM bearings covered by this specification are illustrated by Figs. 1-4. Most PMbearings are small and weigh less than one-quarter pound (100 g) but they can be produced in sizes that will accommodate shaftsup to approximate
45、ly 8 in. (200 mm) in diameter.10.3 Permissible variations in dimensions shall be within the tolerance limits shown on the bearing print accompanying theorder or shall be within the limits specified in the purchase order or contract. Dimensional tolerances of bearings for military orgovernment applic
46、ations shall meet the requirements specified in the Supplementary Requirements section.10.4 Recommended commercial tolerances for bronze-base PM bearings are referenced throughout the tables in Appendix X2.10.5 Chamfers of 30-45 are generally used on PM bearings to break the corners.TABLE 1 Specific
47、ations for Bronze-Base Materials used in PM BearingsMaterial Designation CodeChemical Requirements PhysicalRequirements Mechanical RequirementsCoppermass %Tinmass %Leadmass %GraphiticCarbonmass %Ironmass %AllOthersmass %Radial CrushingStrength, KImpregnatedDensityg/cm3ContentOilvol %103 psi (MPa)Bro
48、nze (Low Graphite)CT-1000-K19 bal 9.5-10.5 0.3 max 1.0 max 1.0 max 6.0-6.4 24 minA,G 19 min (130 min)CT-1000-K26 bal 9.5-10.5 0.3 max 1.0 max 1.0 max 6.4-6.8 19 minG 26 min (180 min)CT-1000-K37 bal 9.5-10.5 0.3 max 1.0 max 1.0 max 6.8-7.2 12 minG 37 min (260 min)CT-1000-K40 bal 9.5-10.5 0.3 max 1.0
49、max 1.0 max 7.2-7.6 9 minG 40 min (280 min)Bronze-GraphiteBronze (Medium Graphite)CTG-1001-K17 bal 9.5-10.5 0.5-1.8 1.0 max 1.0 max 6.0-6.4 22 minB,G 17 min (120 min)CTG-1001-K23 bal 9.5-10.5 0.5-1.8 1.0 max 1.0 max 6.4-6.8 17 minG 23 min (160 min)CTG-1001-K30 bal 9.5-10.5 0.5-1.8 1.0 max 1.0 max 6.8.7.2 9 minG 30 min (210 min)CTG-1001-K34 bal 9.5-10.5 0.5-1.8 1.0 max 1.0 max 7.2-7.6 7 minG 34 min (230 min)Bronze-High GraphiteBronze (High Graphite)CTG-1004-K10 bal 9.2-10.2 2.5-5.0 1.0 max 1.0 max 5.8-6.2 11 min
