1、 - STD*AECMA PREN 4253-ENGL 1777 1OL2311 OOL2Lbb dB1 M Edition approved for publication 1 997-0 1 -3 1 AECMA STANDARD NORME AECMA AECMA NORM Comments should be sent within six months after the date of publication to AECMA Gulledelle 94 B-1200 BRUXELLES prEN 4253 Edition P 1 January 1997 PUBLISHED BY
2、 THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - 8-1200 BRUXELLES - Tel. (32) 2 775 81 10 - Fax. (32) 2 775 81 11 ICs : 49.040.20 Descriptors : ENGLISH VERSION Aerospace series Nuts, anchor, self-locking, fixed, closed corner, reduced series with counterbore, in heat resisti
3、ng steel, silver plated Classification : 1 100 MPa (at ambient temperature) / 425 OC Srie arospatiale crous river, freinage interne, fixes, dangle, srie rduite, avec chambrage, en acier rsistant chaud, argents Classification : 1 100 MPa ( temprature ambiante) 1425 OC Luft- und Raumfahrt Annietmutter
4、n, selbstsichernd, einseitiger verkurzter Eckflansch, mit zylindrischer Aussenkung, aus hochwarmfestem Stahl, versilbert Klasse : 1 100 MPa bei Raumtemperatur) I425 OC This “Aerospace Series“ Prestandard has been drawn up under the responsibility of AECMA (The European Association of Aerospace Indus
5、tries). It is published on green paper for the needs of AECMA-Members. It has been technically approved by the experts of the concerned Technical Committee following comment by the Member countries. Subsequent to the publication of this Prestandard, the technical content shall not be changed to an e
6、xtent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and signature of the AECMA Standard Checking Centre INPS) and formal agreement of the Official Services of the Member countries it will be submitted as a draft European
7、 Standard to CEN (European Committee for Standardization) for formal vote. Nota - Extra copies can be supplied by B.N.A.E. - Technopolis 54 - 199, rue Jean-Jacques Rousseau - 921 38 ICCY-LES-MOULINEAUX CEDEX C3 Chairman Mr Arena I aecma 1997 Copyright Association Europeene des Constructeurs de Mater
8、iel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-STD-AECMA PREN 4253-ENGL 1997 H LO123LL 00L2Lb7 7L W Page 3 prEN 4253 1 Scope This standard specifies the characteristics of self-locking, fixed closed corner, a
9、nchor nuts, reduced series with counterbore, in heat resisting steel, silver plated. Classification : 1 100 MPa l) / 425 “C *) 2 Normative references IS0 3222 Aerospace - Nuts, anchor, self-locking, fixed, closed corner, reduced series, with counterbore, with MJ threads, coated or non uncoated, clas
10、sification 1 100 MPa / 235 “C, 1 1 O0 MPa /315“C or 1 100 MPa / 425C - Dimensions IS0 5855-2 Aerospace - MJ threads - Part 2 : Limit dimensions for bolts and nuts IS0 5858 Aerospace - Self-locking nuts with maximum operating temperature less than or equal to 425 “C - Procurement specification IS0 87
11、88 Aerospace - Fasteners - Tolerances of form and position for nuts EN 2000 Aerospace series - Quality assurance - EN aerospace products - Approval of the quality system of manufacturers EN 2424 Aerospace series - Marking of aerospace products EN 2786 Aerospace series - Electrolytic silver plating o
12、f fasteners 3, EN 3042 Aerospace series - Quality assurance - EN aerospace products - Qualification procedure TR 3791 Aerospace series - Materials for all metal self-locking nuts and thin wall inserts of temperature classes I 425 “C 4, 1) Corresponds to the minimum stress which the nut is able to wi
13、thstand at ambient temperature, without breaking or cracking when tested with a bolt of a higher strength class. 2) Maximum temperature that the nut is able to withstand, without permanent alteration to its original charac- teristics, after ambient temperature has been restored. The maximum temperat
14、ure is conditionned by the surface treatment. 3) Published as AECMA Prestandard at the date of publication of this standard 4) Published as AECMA Technical Report at the date of publication of this standard Previous page is blank Copyright Association Europeene des Constructeurs de Materiel Aerospat
15、ial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-STD-AECMA PREN 4253-ENGL 1777 = 10L231Z 00L21bA b54 W Page 4 prEN 4253 3 Required characteristics 3.1 Configuration - Dimensions - Masses See Figure 1 and Table 1. Dimension
16、s and tolerances are : in conformity with IS0 3222, expressed in millimetres and apply after surface treatment. Details of form not stated are at the manufacturers option. The cap shall remain joined (type of attachment at the user?s discretion) to the nut at the maximum operating temperature. See t
17、est conditions in IS0 5858. 3.2 Tolerances of form and position IS0 8788 3.3 Materials TR 3791 3.4 Surface treatment EN 2786, thickness : - on external surfaces: 5 pm to 15 pm ; - on pitch diameter : 5 prn minimum for nuts MJ6. Nuts MJ5 and smaller shall show complete coverage over complete profile.
18、 Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Page 5 prEN 4253 Remove sharp edges 0,1 to 0,4 I Y-Y b chamfer 1) These values in micrometres apply be
19、fore to surface treatment. They do not apply to threads, punched holes or sheared edges, the surface texture of which will be as achieved by usual manufacturing methods. 2) Tooling marks are permitted in this area. Figure 1 Table 1 1) In accordance with IS0 5855-2. In the self-locking zone the toler
20、ances apply before forming out-of-round .2) Measured at sharp comers (chamfered) or point of tangency (radiused) 3) Measured at rivet hole location 4) Maximum protrusion of the bolt 5) Approximate values (kg/l 000 pieces), given for information purposes only. They apply to anchor nuis without cap I
21、Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,- - - STD-AECMA PREN 4253-ENGL 1777 1012311 OOLZL70 202 = without with Page 6 prEN 4253 - (hyphen) B 4 D
22、esignation EXAMPLE : Description block Identity block EN4253-060 -T Nunber of this standard Cap code (see table 2) Diameter code (see table 1) I NOTE : If necessary, the code 19005 shall be placed between the description block and the identity block. Table 2 I I Code I 5 Marking EN 2424, style N. Se
23、e figure 1. 6 Technical specification IS0 5858 except for : - Approval of manufacturers : see EN 2000 ; - Qualification of products : see EN 3042. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
