1、A.E.C.M.A. STANDARD NORME A.E.C.M.A. A.E.C.M.A. NORM Edition approved for publication 14 th September 1987 prEN3285 issue P 1 September 1987 Comments should be sent within six months CI Chairman after the date of publication decision 88, Bd. Malesherbes A.E.C.M.A. Mr. MOUTARDE 75008 PARIS - FRANCE D
2、ITE PAR LASSOCIATION EUROPEENNE DES CONSTRUCTEURS DE MATERIEL AEROSPATIAL 88, boulevard Malesherbes, 75008 PARIS -TEL. 45-63-82-85 UDC : 629.7.02 : 621.822.74.004.1 : 669.14 : 669.738 Key words : Aircraft industry, airframe bearings, ball bearings, steel, cadmium, dimensions, static loads ENGLISH VE
3、RSION Aerospace series Bearings-airframe rolling rigid, single row ball bearings in steel, cadmium plated diameter series O and 2 normal clearance category Dimensions, torques, and loads Srie arospatiale Luft- und Raumfahrt Roulements pour structures daronefs Flugwerklager roulements rigides une ran
4、ge de billes en acier, cadmis sries de diamtres O et 2 catgorie jeux normaux Dimensions, couples et charges einreihige Rillenkugellager aus Stahl, verkadmet Durchmesserreihen O und 2 normale Lagerluft Mape, Momente und Belastungen This Aerospace Series pre-standard has been drawn up under the respon
5、sibility of AECMA (Association Europenne des Constructeurs de Matriel Arospatial). It is published on green paper for the needs of AECMA-Members. It has been technically approved b y the experts of the concerned AECMA Commission following comment by the Member countries. Subsequent to the publicatio
6、n of this pre-standard, the technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and signature of the AECMA Standard Checking Centre (NPS) and formal agreement of the Official
7、 Services of the Member countries it will be submitted as a draft European Standard to CEN (European Committee for Standardization) for final vote. L. aecma 1987 AECMA PREN3285 87 m 10L23LL 0005236 T prEN3285 Page 2 Foreword The characteristics of the bearings covered by this standard are identical
8、to those of EN2013 with regard to configuration, dimensions, tolerances, mass and loads. They differ from them by the addition of new characteristics : - starting torques ; - internal axial clearances ; - special group for the internal radial clearance. AECMA _ PEEN3285 - 87 W LOL23LL 0005237 -_-_A
9、L W prEN3285 Page 3 1 Scope This standard speclfies the characteristics of rigid single row ball bearings of diameter series O and 2 1) designed to withstand only slow rotations and oscillations under load. 0 They are intended or use between fixed and moving parts of the aircraft structure and their
10、 control mechanisms. 2 Field of application The airframe rolling bearings defined in this standard shall be used from -54 to 4-150 C. However, being lubricated wTth the following greases : - very high pressure grease, ester type (code A), operational range -73 to +121 OC or - very high pressure grea
11、se, synthetic hydrocarbons, general purpose (code B), operational range -54 to t-177 OC (refer to EN3280) ; their field of application when lubricated with code A grease shall be limited to i-121 OC 3 References IS0 15-1981, Rolling bearings - Radial bearings - Boundary dimensions - General plan IS0
12、 1132-1980, Rolling bearings - Tolerances - Definitions EN2031, Steel FE-PL31 - Hardened and tempered - Bars - Aerospace serfes EN2133, Cadmium plating of steels with maximum specified tensile strength equal to or less than 1450 FPa and copper and copper alloys - Aerospace series Steel FE-PL31 - Har
13、dened and tempered - Hollow bars 3,5 mm - a 5 55 mm - Aerospace series EN2221, EN2222, Steel FE-PL31 - Hardened and tempered - Hand and die forgings - Aerospace series EN3280, Bearings - airframe rolling - Technical specification - Aerospace series 4 Definition Rigid bearings, full complement of bal
14、ls (without cage), single row of balls with filling clot. 1) See IC0 15. O AECMA PREN3285 87 W 1012311 0005238 3 prEN3285 Page 4 5 Symbols The definition of tolerances and of clearances are given in IS0 1132 and definition of loads in EN3280. dmp Dmp ds Ds C F max.= permissible static axial load Ga
15、= axial internal clearance Ga = radial internal clearance r Kea Kia ea ia = single plane mean bore diameter = single plane mean outside diameter = deviation of a single bore diameter = deviation of a single outside diameter = permissible static radial load S = radial runout of assembled bearing oute
16、r ring = radial runout of assembled bearing inner ring = assembled bearing outer ring face runout with raceway (groove) = assembled bearing inner ring face runout with raceway (groove) = coefficient of axial load 6 Required characteristics 6.1 Dimensions - Tolerances - Clearances - Loads - Mass Valu
17、es : see table ; the bearings and tolerances apply after protection, Configuration : see figure ; the bearings can be assembled with either seals or shields. 6.2 Surface roughness Raceway and rolling elements : Ra = 0,2 pm Bore, side faces and cylindrical outer surface : Ra = 0,8 pm. The values appl
18、y prior to cadmium plating. 6.3 Materials Inner ring : Steel EN2031 or EN2221 or EN2222, 59 to 64 HRC 1). Outer ring : Steel EN2031 or EN2221 or EN2222, 59 to 64 HRC 1). Balls : Steel EN2031, 59 to 64 HRC 1). Shields : Corrosion resisting material. Seals : Polytetrafluoroethylene (PTFE) or polytetra
19、fluoroethylene (PTFE), coated glass fabric material. 6.4 Surface treatment Cadmium plating (type of passivation optional), 5 to 12 pm, of the inner and outer rings, the bore and raceway are not cadmium plated. Cadmium plating shall be in accordance with EN2133. As soon as possible after plating, and
20、 within 16 hours de-embrittlement heat treatment shall be carried out at a temperature and for a time (compatible with the performance requirements of the bearing) which shall be subject to written approval of the qualifying authorities. 1) For new designs, bearings in corrosion resisting steel shou
21、ld be used preferably, see EN3286. C 05 06 08 10 12 15 17 20 25 30 Bearing with shields - Gode Ga Gr (Sa) 5 6 8 10 12 15 3 to 18 17 120 20 25 5 to 20 30 150 100 2 to 13 40 P E Detail W applicable to bore and outer surface The process for installation of seails and shields is at the manufacturers opt
22、ion. Figure 1 tolerances pm I 1 Il) Deftnition : see EN3280 I where Y = 2,2 S radial load Axial and radial loads may be applied simultaneously. For ultimate static loads, see EN3280. AECMA PREN3285 87 LOL231L 0005240 L prEN3285 Page 6 7 Designation Each bearing shall only be designated as in the fol
23、lowing example : Description block Identity block I Number of EN standard I 10 = diameter code of d (see table) A = Code for ester type grease P = code for type with shields where the following codes are applied : Greases A = ester type grease , B = synthetic hydrocarbon type grease Types E = with s
24、eals P = with shields Note : If necessary, the originator code S9005 may be introduced between the description block and the identity block. 8 Marking In addition to the manufacturers own marking, each bearing shall be marked, on one side face only using the identity block as defined in clause 7 of this standard. Marking position and method are at the manufacturers option. 9 Technical specification Bearings supplied to this standard shall conform with the requirements of EN3280.
