1、_SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising theref
2、rom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2010 SAE International All rights reserved. No part of this publication ma
3、y be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-4970 (outside US
4、A) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/AS8943AEROSPACESTANDARDAS8943 Issued 2010-08Bearings, Sleeve, Plain and Flanged, Self Lubricati
5、ng -65 to +250 F RATIONALEThis procurement document and its corresponding parts sheets are being updated and re-formatted from MIL-B-8943 to the SAE standard. NOTICEThis document has been taken directly from U.S. Military Specification MIL-B-8943A and contains only minor editorial and format changes
6、 required to bring it into conformance with the publishing requirements of SAE technical standards. The initial release of this document is intended to replace MIL-B-8943A. Any part numbers established by the original specification remain unchanged. The original Military Specification was adopted as
7、 an SAE standard under the provisions of the SAE Technical Standards Board (TSB) Rules and Regulations (TSB 001) pertaining to accelerated adoption of government specifications and standards. TSB rules provide for (a) the publication of portions of unrevised government specifications and standards w
8、ithout consensus voting at the SAE Committee level, and (b) the use of the existing government specification or standard format. Under Department of Defense policies and procedures, any qualification requirements and associated Qualified Products Database are mandatory for DOD contracts. Any require
9、ment relating to Qualified Products Database (QPDs) has not been adopted by SAE and is not part of this technical report. 1. SCOPE 1.1 This standard covers plain and flanged sleeve bearings which are self-lubricating by incorporating polytetrafluoroethylene (PTFE) in a liner in the bore for use in a
10、 temperature range of -65 to +250 F (-54 to +121 C). 2. APPLICABLE DOCUMENTS The following publications form a part of this document to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date o
11、f the purchase order. In the event of conflict between the text of this document and references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 2.1 SAE Publications
12、Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.AS8243 Anti-icing fluid and Deicing Defrosting Fluids AS21240 Bearing, Sleeve, Plain, PTFE Lined AS21241 Bearing, Sleeve, Flanged,
13、 PTFE Lined SAE AS8943 Page 2 of 122.2 ANSI/ASME Publications Available from American National Standards Institute, 25 West 43rd Street, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org or American Society of Mechanical Engineers, 22 Law Drive, P.O. Box 2900, Fairfield, NJ 07007-2900, Tel: 9
14、73-882-1170, www.asme.org .ANSI/ASME B46.1 Surface Texture (Surface Roughness, Waviness and Lay) ANSI/ASME Y14.100 Engineering Drawing Practices 2.3 ASTM Publications Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.ast
15、m.org.ASTM C794 Standard Test Method for Adhesion-in-Peel of Elastomeric Joint Sealants ASTM F25 Standard Test Method for Sizing and Counting Airbourne Particles ASTM F50 Standard Practice for Continuous Sizing and Counting of Airbourne Particles 2.4 U.S. Government Publications Available from the D
16、ocument Automation and Production Service (DAPS), Building 4/D, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Tel: 215-697-6257, http:/assist.daps.dla.mil/quicksearch/.MIL-A-8625 Anodic Coatings for Aluminum and Aluminum Alloys MIL-STD-2073-1Standard Practice for Military Packaging MIL-DTL-197 Pa
17、ckaging of Bearings, Anti-Friction, Associated Parts and Subassemblies MIL-PRF-5606 Hydraulic Fluid, Petroleum Base, Aircraft, Missile, and Ordinance MIL-DTL-5624 Turbine Fuel, Aviation, Grades JP-4, JP-5 and JP-5/JP-8ST MIL-PRF-7808 Lubricating Oil, Aircraft Turbine Engine, Synthetic Base MIL-DTL-5
18、541 Chemical Conversion Coatings on Aluminum Alloys MIL-STD-129 Standard Practice Military Marking for Shipment and Storage 3. REQUIREMENTS 3.1 Aerospace Standard (AS) Sheets The individual item requirements shall be as specified herein and in accordance with the applicable AS sheets. In the event o
19、f any conflict between the requirements of this standard and the AS sheet, the latter shall govern. 3.2 Qualification The bearings furnished under this standard shall be a product which is in accordance with the applicable Aerospace Standard (AS) and which has been subjected to and which has passed
20、the qualification tests specified herein, and which has been listed on or approved for listing on the applicable Qualified Products Database (QPD). SAE AS8943 Page 3 of 123.2.1 Product Change Any change in product design, description, materials, processing, procedures or plant location shall be repo
21、rted to the qualifying activity and may require requalification of the product to an extent determined by the qualifying activity. Any other specific changes, which must be brought to the qualifying activities attention, shall be identified in the qualification notification letter. 3.2.2 Product Man
22、ufacture Except for the bonding operations, the manufacturer is permitted to subcontract manufacturing operations without violating the requirements of 3.2.1. The bonding operations shall be performed in the plant listed on the Qualified Products Database. Manufacture of the self-lubricating liner m
23、aterial may also be subcontracted. Any change in (1) the liner manufacturer, (2) the liner manufacturing procedures, or (3) the materials used in manufacture of the liner will require requalification to an extent determined by the qualifying activity. The manufacturer is responsible for meeting all
24、requirements of the standard and for the quality of the end product, whether it is manufactured totally in-house or some of the operations are performed by a subcontractor. Inherent in the responsibility for the end product is the responsibility to verify that the subcontractors processes meet stand
25、ard requirements. 3.3 Materials Material for the sleeve and liner shall be in accordance with the applicable AS sheet. PTFE shall be included in the liner in such a manner that the bearing will conform to all requirements of this standard. 3.3.1 Aluminum Finishes Aluminum sleeve bearings shall be an
26、odized per MIL-A-8625, Type I or II.3.4 Design Bearing design shall conform to that shown on AS21240 and AS21241. 3.5 Construction The liner shall be so secured that all relative motion will be between the liner and the shaft. Except as otherwise specified on the applicable AS sheet, the details of
27、the design shall be optional. 3.5.1 Dimensions and Tolerances Dimensions and tolerances shall be as specified on the applicable AS sheet. Dimensions not shown shall be at the option of the manufacturer. 3.5.2 Surface Texture The surface texture shall be in accordance with the applicable AS sheet and
28、 ANSI/ASME B46.1. Bearings shall be free of any surface defects, which may be detrimental to satisfactory installation, performance or bearing life as defined in this standard. Unless otherwise specified, liner surfaces are exempt from surface texture measurements. 3.5.3 Lubrication Initial grease o
29、r oil lubrication by the manufacturer will not be permitted.3.5.4 PTFE Liner Condition SAE AS8943 Page 4 of 123.5.4.1 Visual Examination The visual appearance of the bonded liner shall exhibit a degree of workmanship consistent with proper manufacturing process controls, as checked per 4.6.5.1. The
30、liner shall be uniform in texture and shall contain no imbedded contaminants. The liner setback shall meet the applicable drawing requirements. There shall be no separation or lifting of the liner at any of the edges. Unraveling and fraying is not permitted outside the setback area. Molded liners sh
31、all not contain embedded contaminants, cracks, or bubbles. 3.5.4.2 Bond Integrity and Peel Strength When tested in accordance with 4.6.5.2, the liner shall be tightly adherent to the metallic substrate over at least 90% of the contact area and shall exhibit an average peel strength of 2 lb per sq in
32、ch or greater. The adhesive remaining on the metal substrate shall have no void or unbonded area which cannot be included within a circumscribing circle with a diameter equal to 25% of the lined sleeve length or 0.25 inch, whichever is smaller. 3.5.4.2.1 Processing Controls All fabrication of the PT
33、FE liner involving application or mixing of adhesive, and all liner bonding procedures involving application of adhesive, shall be conducted in a controlled area.3.5.4.2.1.1 Controlled Area The controlled area shall be maintained at a temperature of 75 10 F with a maximum relative humidity of 75%. T
34、he enclosed atmosphere of the work area shall be well ventilated and maintained so that the particle count is 2500/ft3maximum for particles 5.0 microns or larger when measured per ASTM F 25 or ASTM F 50. The particle count measurement shall be performed annually (minimum). There shall be no eating o
35、r smoking in the controlled area and no process which produces uncontrolled spray, dust, fumes, or particulate matter.3.5.4.3 Liner Peelability Each manufacturer shall establish during qualification testing whether the liner is peelable or non-peelable. If peelable, the manufacturer shall determine
36、the mean and standard deviation peel strength values for the liner based upon a minimum of six peel strength tests conducted in accordance with 4.6.6.2. This data shall be recorded in the qualification test report. A liner originally qualified as non-peelable shall remain peelable in production. A l
37、iner originally qualified as non-peelable shall remain non-peelable in production. 3.6 Performance 3.6.1 Radial Static Limit Load After the radial load listed in Table 1 has been applied as specified in 4.6.1, the permanent set shall be less than 0.004 inch.3.6.2 Oscillation under Radial Load The to
38、tal liner wear of the bearing shall not exceed 0.006 inch when tested in accordance with 4.6.2 with the radial unidirectional load listed in Table 1. Visual examination of the liner after test shall indicate no loss of bonding to the metalsubstrate in the loaded area. TABLE 1 - LOAD VALUESPart No. R
39、adial Static Limit Load (lbs.)Oscillation Load (lbs.)After Test Breakaway Torque(in/lbs. max.) MS21240-08A012 9100 6000 75 -08C012 9100 6000 75 -16A016 26 400 12 100 300 -16C016 26 400 12 100 300 -24A016 39 600 15 200 570 -24C016 39 600 15 200 570 SAE AS8943 Page 5 of 123.6.3 Fluid Compatibility Whe
40、n tested in accordance with 4.6.3, the bearings shall be compatible with the fluids listed in 4.6.3 and the total liner wear shall not exceed 0.006 inch. Visual examination of the liner after test shall indicate no loss of bonding to the metal substrate in the loaded area. 3.6.4 Corrosion Resistance
41、 Corrosion resistance shall be determined in accordance with MIL-STD-810 Method 507.5. Superficial tarnish which can be removed with a damp cloth will not be cause for rejection. 3.6.5 High Temperature When tested in accordance with 4.6.5, under the oscillating load specified on the applicable AS sh
42、eet, the total liner wear shall not exceed 0.006 inch. Visual examination of the liner after test shall indicate no loss of bonding to the metal substrate in the loaded area. 3.7 Interchangeability All parts having the same manufacturers part number shall be directly and completely interchangeable w
43、ith each other and with respect to installation and performance. The drawing number requirements of ANSI/ASME Y14.100 shall govern changes in the manufacturers part numbers. 3.8 Identification of Product Each bearing shall be permanently and legibly marked with the manufacturers CAGE code, manufactu
44、rers lot number, and Aerospace Standard part number as a minimum. Metal impression stamping is prohibited. 3.9 Workmanship The bearings shall be free of toolmarks, chatter waves, rust, grinding scratches, pits, or other defects that may adversely affect their serviceability. 4. QUALITY ASSURANCE PRO
45、VISIONS 4.1 Responsibility for Inspection Unless otherwise specified in the contract or purchase order, the supplier is responsible for the performance of all inspection requirements as specified herein. Except as otherwise specified, the supplier, may utilize his own facilities or any other commerc
46、ial laboratory acceptable to the Government. The Government reserves the right to perform any of the inspections set forth in the standard where such inspection are deemed necessary to assure supplies and services conform to prescribed requirements. 4.1.1 Qualification Test Records The manufacturer
47、shall maintain a record showing quantitative results for all tests required by this standard. This record shall be available to the purchaser and shall be signed by an authorized representative of the manufacturer or the testing laboratory, as applicable. 4.2 Classification of Tests The inspection a
48、nd testing of the bearings shall be classified as: a. Qualification tests (4.3) b. Quality conformance tests (4.4) SAE AS8943 Page 6 of 124.3 Qualification Tests 4.3.1 Sampling Instructions Qualification test samples shall consist of 15 bearings conforming to MS21240-08A012 plus 15 bearings of each
49、type (plain or flanged) of the following sizes, widths, and housing materials specified in column I of Table 2 for which qualification is desired. Corresponding bearings in column II of Table 2 will be qualified on the basis of similarity. All bearings necessary for tests specified herein shall be furnished by the manufacturer. Samples shall be identified as required and forwarded to the activity designated in the letter of au
