1、AEROSPACE STANDARDBEARING, BALL, AIRFRAME, ANTI-FRICTION, EXTERNAL SELF-ALIGNING, EXTRA LIGHT DUTYCORROSION RESISTANT NITROGEN STEEL (CREN)AS27648/1Copyright 2017 SAE InternationalAll rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any
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3、p:/www.sae.orgISSUED2017-02THIRD ANGLE PROJECTIONCUSTODIAN: ACBGFEDERAL SUPPLY CLASS3110AS27648/1SHEET 1 OF 4PROCUREMENT SPECIFICATION: AS7949SAE Technical Standards BoardRules providethat:“This reportis publishedby SAE to advance thestateoftechnical andengineering sciences. The useofthis reportis e
4、ntirely voluntary, and its applicability and suitability forany particularuse, includingany patent infringement arising therefrom,is thesole responsibility of theuser.”SAE reviews eachtechnical reportatleastevery fiveyears at whichtime it may berevised, reaffirmed, stabilized, or cancelled. SAEinvit
5、es your written comments and suggestions.SAE values your input. To provide feedback on thisTechnical Report, please visit http:/standards.sae.org/AS27648/1 RATIONALETHIS STANDARD DEFINES A CORROSION RESISTANT NITROGEN STEEL (CREN) VERSION OF THE AS27648 EXTRA LIGHT DUTY AIRFRAME BALL BEARING SERIES.
6、NOTICETHE COMPLETE REQUIREMENTS FOR PROCURING THE PRODUCT DESCRIBED HEREIN SHALL CONSIST OF THIS DOCUMENT AND THE LATEST ISSUE OF AS7949.FIGURE 1 - PART CONFIGURATIONAEROSPACE STANDARDAS27648/1SHEET 2 OF 4BEARING, BALL, AIRFRAME, ANTI-FRICTION, EXTERNAL SELF-ALIGNING, EXTRA LIGHT DUTYCORROSION RESIS
7、TANT NITROGEN STEEL (CREN)TABLE 1 - DIMENSIONSASDASHNO.B BORE2/BORE TOLERANCED OUTSIDEDIAMETER+.0000-.00101/ 2/WWIDTHINNERRING+.000-.0051/HWIDTHOUTERRING+.000-.0051/(A)SHOULDERDIAMETERINNERRING(APPROX)E4/C3/KTOSHARP CORNER (REF)JBRG. SPHERE OUTSIDE DIAMETERLMISALIGNMENT ANGLE EITHER DIRECTION5/WEIGH
8、TPOUNDS(APPROX)CORNER CHAMFER X 45INNERRING BORE+.015-.000OUTERRING OD+.015-.000-16 1.0000 +.0000 -.0005 1.9375437 .3751.141.024 .0241.709 1.740 7 25 .18-21 1.3125+.0005-.00052.2500 1.454 2.028 2.052 6 30 .20-23 1.4375 2.3750 1.575 2.155 2.178 6 .22-25 1.5625 2.5000 1.693 2.282 2.302 5 45 .25-29 1.8
9、125 2.7500 1.931 2.535 2.552 5 .27-33 2.0625 3.0000 2.231 2.787 2.802 5 .30-37 2.3125 3.2500 2.468 3.039 3.052 4 30 .33-47 2.9375 4.1250.531 .4693.093.039 .0393.846 3.865 4 30 .64-48 3.0000 4.2500 3.222 3.972 3.990 4 .69-49 3.0625 4.2500 3.222 3.972 3.990 4 .691/ ALL DIMENSIONS TO BE MET AFTER SURFA
10、CE TREATMENT.2/ OUT-OF-ROUND TOLERANCES: BORE: -16 +.0003, -.0008 -21 THROUGH -49 +.0008, -.0008 OUTER DIA: +.0010, -.0020.3/ A RADIUS GIVING APPROXIMATELY THE SAME GRIP FOR STAKING THE BEARING IN THE HOUSING WILL BE ACCEPTABLE.4/ A RADIUS GIVING APPROXIMATELY THE SAME FILLET CLEARANCE WILL BE ACCEP
11、TABLE.5/ MISALIGNMENT ANGLE IS NOT TO EXCEED MINIMUM REQUIREMENT IN DESIGN OR APPLICATION.TABLE 2 - LOADS AND STARTING TORQUEASDASHNO.RADIALLIMITLOADRATINGLBTHRUSTLIMITLOADRATINGLB6/ 7/RADIAL LOAD RATING(LB) FOR AVERAGELIFE OF 10000COMPLETE 90 CYCLES8/MAXIMUM STARTING TORQUE(INCH-OUNCE)CASE I CASE I
12、I-16 8085 1600 4260 3960 5.0-21 9840 2000 4590 4290 7.0-23 10500 2200 4650 4360 9.0-25 11300 2300 4680 4420 9.0-29 12700 2600 4760 4530 14.0-33 14400 2900 4820 4630 14.0-37 15800 3200 4880 4690 20.0-47 24700 5000 6600 6390 30.0-48 27500 5500 8150 7840 30.0-49 27500 5500 8150 7840 32.06/ CASE I - LOA
13、D FIXED WITH RESPECT TO OUTER RING.CASE II - LOAD FIXED WITH RESPECT TO INNER RING.7/ THESE RATINGS ARE FOR OPERATION UP TO 250 F. FOR OPERATION UP TO 350 F, THE RATINGS SHALL BE REDUCED BY 20%.8/ SPECIFIED LIMITS ARE FOR BEARINGS LUBRICATED WITH MIL-PRF-81322 GREASE. FOR BEARINGS LUBRICATED WITH MI
14、L-PRF-23827 TYPE I GREASE, THE TORQUE LIMIT SHALL BE THE SPECIFIED VALUE IN THE TABLE MULTIPLIED BY 1.2.AEROSPACE STANDARDAS27648/1SHEET 3 OF 4BEARING, BALL, AIRFRAME, ANTI-FRICTION, EXTERNAL SELF-ALIGNING, EXTRA LIGHT DUTYCORROSION RESISTANT NITROGEN STEEL (CREN)REQUIREMENTS1. MATERIAL:RINGS: CORRO
15、SION RESISTANT NITROGEN STEEL (CREN) PER AMS5898, AMS5925 OR AISI 422 STEEL PER AMS5655.BALLS: NO SUFFIX CODE CORROSION RESISTANT NITROGEN STEEL (CREN) PER AMS5898 OR AMS5925.SUFFIX CODE “T” CORROSION RESISTANT STEEL (CRES) PER AMS5880 OR AMS5618. CRES BALLS SHALL BE PASSIVATED IN ACCORDANCE WITH AM
16、S2700, METHOD 1 (NITRIC ACID) OR METHOD 2 (CITRIC ACID), OR ASTM A967/A967M, CITRIC I, II, OR IIIAMS2700 METHOD 1, TYPE 8 SHALL NOT BE USED.SEALS: POLYTETRAFLUOROETHYLENE (PTFE) PER AMS3652SEAL RETAINERS: ANY CORROSION RESISTANT STEEL2. HARDNESSRINGS: STEEL PER AMS5898 AND AMS5925 THROUGH HARDEN TO
17、58 HRC MINIMUM.STEEL PER AMS5655: RING WALL THICKNESS .090 OR LESS: CASE HARDEN 58 HRC MINIMUM AT A CASE DEPTH OF 1/3 WALL THICKNESSRING WALL THICKNESS GREATER THAN .090: CASE HARDEN 58 HRC MINIMUM AT A CASE DEPTH OF .030BALLS: 58 HRC MINIMUM3. STABILITYRINGS AND BALLS SHALL BE STABILIZED FOR OPERAT
18、ION UP TO 250 F.4. LUBRICANTALL BEARINGS SHALL BE PACKED WITH AN 80% MINIMUM GREASE FILLNO SUFFIX CODE MIL-PRF-81322 GREASESUFFIX CODE “G” MIL-PRF-23827 TYPE I GREASE MIL-PRF-23827 TYPE I GREASE SHALL NOT BE USED FOR OPERATION WHERE TEMPERATURES EXCEED 250 F5. SURFACE ROUGHNESSRACEWAYS AND BALLS SHA
19、LL HAVE A MAXIMUM SURFACE ROUGHNESS OF 8 MICROINCHES Ra PER ANSI/ASME B46.16. SURFACE TREATMENTNO SUFFIX CODE ALL EXTERNAL SURFACES EXCEPT BORE, SEALS AND SEAL RETAINERS SHALL BE PLATED WITH CADMIUM PER AMS-QQ-P-416, TYPE I, CLASS 2, .0003 TO .0006 THICKSUFFIX CODE “E” ALL EXTERNAL SURFACES EXCEPT B
20、ORE, SEALS AND SEAL RETAINERS SHALL BE PLATED WITH ZINC NICKEL PER AMS2417, TYPE 2, GRADE B, .0003 TO .0006 THICKSUFFIX CODE “P” ALL RING SURFACES SHALL BE PASSIVATED PER AMS2700 METHOD 1 (NITRIC ACID) OR METHOD 2 (CITRIC ACID), OR ASTM A 967, CITRIC I, II, OR III.AMS2700 METHOD 1, TYPE 8 SHALL NOT
21、BE USED7. RADIAL INTERNAL CLEARANCE: .0003 TO .0010DOES NOT INCLUDE RADIAL LOOSENESS BETWEEN THE BEARING OUTER RING AND SELF-ALIGNING RINGAEROSPACE STANDARDAS27648/1SHEET 4 OF 4BEARING, BALL, AIRFRAME, ANTI-FRICTION, EXTERNAL SELF-ALIGNING, EXTRA LIGHT DUTYCORROSION RESISTANT NITROGEN STEEL (CREN)8.
22、 RADIAL AND LATERAL ECCENTRICITYINNER RING, .0010 MAX.OUTER RING, .0016 MAX.9. PART NUMBERTHE PART NUMBER SHALL BE SEQUENCED LEFT TO RIGHT WITHOUT SPACES WITH DESIGNATIONS IN THE FOLLOWING SEQUENCE:10. EXAMPLE OF PART NUMBER:AS27648/1 -16 G E T = BEARING, BALL, AIRFRAME, ANTIFRICTION, EXTERNAL SELF
23、ALIGNING, EXTRA LIGHT DUTY, CREN 1.0000 INCH +.0000, -.0005 BORE, .0001 TO .0005 INCH RADIAL INTERNAL CLEARANCE, FILLED 80% MINIMUM WITH MIL-PRF-23827 TYPE I LUBRICANT, 250 )0$;:,7+=,1& -NICKEL PLATING AND CRES BALLS PER AMS5880 OR AMS5618BALL MATERIAL CODE (SEE REQUIREMENT 1)SURFACE TREATMENT CODE
24、SEE REQUIREMENT 6)LUBRICANT (SEE REQUIREMENT 4)“AS” DASH NUMBER (SEE TABLE 1)AEROSPACE STANDARD NUMBERNOTESNOTICETHIS DOCUMENT REFERENCES A PART WHICH CONTAINS CADMIUM AS A PLATING MATERIAL. CONSULT LOCAL OFFICIALS IF YOU HAVE QUESTIONS CONCERNING CADMIUMS USE.1. ALL DIMENSIONS ARE IN INCHES, UNLES
25、S OTHERWISE SPECIFIED2. IN THE EVENT OF A CONFLICT BETWEEN THE TEXT OF THIS SPECIFICATION AND REFERENCES CITED HEREIN, THE TEXT OF THIS STANDARD TAKES PRECEDENCE.3. REFERENCED DOCUMENTS SHALL BE OF THE ISSUE IN EFFECT ON DATE OF INVITATION FOR BIDS.4. REVISION INDICATOR: A CHANGE BAR (l) LOCATED IN
26、THE LEFT MARGIN IS FOR THE CONVENIENCE OF THE USER IN LOCATING AREAS WHERE TECHNICAL REVISIONS, NOT EDITORIAL CHANGES, HAVE BEEN MADE TO THE PREVIOUS ISSUE OF THIS DOCUMENT. AN (R) SYMBOL TO THE LEFT OF THE DOCUMENT TITLE INDICATES A COMPLETE REVISION OF THE DOCUMENT, INCLUDING TECHNICAL REVISIONS. CHANGE BARS AND (R) ARE NOT USED IN ORIGINAL PUBLICATIONS, NOR IN DOCUMENTS THAT CONTAIN EDITORIAL CHANGES ONLY.
