ASTM B439-00 pdf free.Standard Specification for Sintered Bronze Bearings (Oil-Impregnated).
The purchase order must specify whether or not thecertification includes chemistry.Upon request of the purchaser in the contract or order,the certification of an independent third party indicatingconformance to the requirements of this specification may beconsidered.
For some materials, supplementary requirements maybe specified. Usually these apply only when specified by thepurchaser in the inquiry, contract, or order. These supplemen-tary requirements shall appear separately.Special Government Requirements——Requirementsthat are special to government needs are listed in 15.2.1through 15.2.9.Materials shall conform to Table 3，Grade 4. Contractor shall furnish a percent composition analysis on anoilfree basis for each lot showing the percentage for eachelement as specified in Table 3.Bearing shall conform to thisspecification and supporting military specification as applicable.High-grade nongumming petroleum lubricants， suchas MIL-PRF-6085，MIL-PRF-17331 (Military Symbol2190_TEP)，or as specified on referenced military standardspecification sheets shall be used to impregnate the bearings.15.2.3 When specified,a first-article inspection shall beperformed on bearings. Four samples shall be made availablefor first-article inspection and tested for chemical require-ments, density, porosity, radial crushing strength, oil excretion,and dimensional characteristics as specified herein，TestMethod B 328，FED-STD-151，or in an otherwise specifieddocument. Any defect or failure shall be cause for rejection ofthe lot. Waivers for minor defects may be addressed to thecontracting officer.
When procured from a contractor versus the actualmanufacturer,a certificate of quality conformance (cooc)supplied by the manufacturer of the bearing may be furnishedin lieu of actual performance of such testing by the contractor,provided lot identity has been maintained and can be demon-strated to the Government. The certificate shall include the name of the contractor，contractor number， name of manufac-turer，NSN, item identification，name of the component ormaterial, lot number,lot size, dimensions， date of testing, testmethod, individual test results, and specification requirements. When specified in the contract or purchase order,packaging and marking shall be completed in accordance withthe provisions of the contract.Oil excretion of the bearing shall be verified byplacing the bearing in the chamber of a preheated oven.Oventemperature shall be nominally 300°F[149°C]. Exposure shallbe 5 min. During the period, beads shall exude uniformly fromthe bearing surface. Lack of appreciable sweating of thelubricant on the bearing surface will be cause for rejection.Lubricant content may be verified using Test Method B 328.15.2.7 Unless otherwise specified, the contractor is respon-sible for testing.The contractor may use their own or any othersuitable facility for the performance of testing and inspection,unless an exception is stated. The Government reserves theright to perform an inspection set forth herein to assuresupplies and sources conform to the prescribed requirements.Records of examination and tests performed by or forthe contractor shall be maintained and made available to theGovernment by the contractor for a period of three years afterdelivery of the products and associate material.
All requirements shall be as specified herein. Refer-ence military standard specification sheets shall take prece-dence unless otherwise specified in the contract or purchaseorder.ASTM B439 pdf download.