1、O O O O Edition approved for publication 1992-03-01 - L Comments should be sent within six months C3 Chairman 7 after the date of publication decision A.E.C.M.A. 88, Bd. Malesherbes Mr. ARENA 75008 PARIS - FRANCE I CEN PREN*3733 93 W 3404589 0030555 O H , _- A.E.C.M.A. STANDARD NORME A.E.C.M.A. A.E.
2、C.M.A. NORM prEN 3713 Issue P 1 March 1991 DIT PAR LASSOCIATION EUROPENNE DES CONSTRUCTEURS DE MATRIEL AEROSPATIAL 88, boulevard Malesherbes, 75008 PARIS -TEL. 45-63-82-85 UDC : Key words ENGLISH VERSION Aerospace series Nuts, self-locking, bhexagonal, Classification : 1550 MPa (at ambient temperatu
3、re) /235 OC steel, cadmium plated, MOS, lubricated Srie arospatiale Luft- und Raumfahrt crous bihexagonaux, freinage interne, en acier, cadmis, lubrifis MOS, Classification : 1550 MPa ( temprature ambiante) /235 OC Zwlfkantmuttern, selbstsichernd, aus Stahl, verkadmet, Mos2 geschmiert Klasse : 1550
4、MPa (bei Raumtemperatur) /235 OC This Aerospace Series pre-standard has been drawn up under the responsibility 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 by the experts of t
5、he concerned Commission following comment by the Member countries. Subsequent to the publication 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
6、 and signature of the AECMA Standard Checking Centre (NPS) and formal agreement of the Official Services of the Member countries it will be submitted as a draft European Standard to CEN (European Committee for Standardization) for final vote. - O O O O CEN PREN*3733 91 m 3404589 O030556 2 m - - - pr
7、EN 3713 Page 3 1 Scope arid field of application This standard specifies characteristics for bihexagonal nuts, with a self-locking feature achieved by forming the upper portion o t-of-rou% in steel, cadmium plated, MOS lubricated, classification 1550 MPa /235 OC , 2 2 References IS0 4095, Fasteners
8、for aerospace construction - Bi-hexagonal wrenching configuration IS0 58.55-2, Aerospace - MJ Threads - Part 2 : Limit dimensions for bolts and nut s IS0 5858, IC0 8788, IS0 9199, EN 2000, EN 2133, EN 2424, EN 2491, EN 3042, EN 3330, EN 3704, Aerospace - Self-locking nuts with maximum operating temp
9、erature less than or equal to 425 OC - Procurement specification 3) Aerospace - Fasteners - Tolerances of form and position for nuts Aerospace - Self-locking bihexagonal nuts, classifications 1100 ElPa/ 650 “C, 1250 MPa/760 OC, 1550 WPa/235 OC and 1550 MPa/650 “C - Dimensions Aerospace series - Qual
10、ity assurance - EN aerospace products - Approval of the quality system of manufacturers 4) Cadmium plating of steels with maximum specified tensile strength equal to or less than 1450 MPa and copper and copper alloys - Aerospace series 4) Aerospace series - Identification marking of standard fastene
11、rs 4) Aerospace series - Molybdenum disulphide dry film lubricants applied to fasteners 3) Aerospace series - Quality assurance - EN aerospace products - Qualification procedure 4) Aerospace series - Steel FE-PL45 - Annealed - Bar and wire De L 40 mm for prevailing torque nuts 5) Aerospace series -
12、Substitute materials for all metal self-locking nuts and thin wall inserts 3) 1) Corresponds to strength class of the associated bolt, the 100 per cent load of which it is able to withstand, when tested at ambient temperature, without breaking or cracking. 2) Maximum temperature that the nut is able
13、 to withstand, without permanent alteration of its original characteristics, after ambient temperature has been restored. The maximurn temperature- is conditioned by the cadmium plating. 3) In preparation at the date of publication of the present standard 4) Published as AECbIG standard at the date
14、of publication of the present standard 5) Published as AECMA pre-standard at the date of publication of the present standard Previous page is blank ICEN PREN*3713 911 m 3404589 00110557 4 m prEN 3713 Poge 4 3 Required characteristics 3.1 See figure and table. 3.2 Materials 1) EN 3330 3.3 Surface tre
15、atment EN 2133, 5 pm minimum on threads and all areas which can be contacted by a 20 mm diameter ball. On all other areas, a continuous cadmium plating shall be present, Configuration - Dimensions - Masses EN 2491, thickness not specified 1) Substitute materials are given in EN 3704. O O O O prEN 37
16、13 Page 5 6,7 pfl I) Remove sharp edges 0,l mm to 0,4 mm x-x - m k$ ? area to achieve the self-locking requirement 5) Figure 6) Table 7) i) These values, fn micrometres, apply before cadmium plating and bios 1.ubrication. The values de not apply to threads, the surface texture of whici will be as ac
17、hieved by usual manufacturing methods. 2) Biliexagonal configuration in accordance with IS0 4095 over length N. 3) All. forms of entry (radius or cham%er) are permissible within these limiting dimensions. 4) Wrench pad engagement 5) Tooling marks are permitted in this area. 6) Details of form, not s
18、tated, are at the manufacturers option. 7) These dimensions are in accordance with IS0 9199. Tolerances of form and position shall be in conformity with IS0 8788. Dimensions and tolerances apply after cadmium plating but before MOS 8) In conformity with IS0 5855-2. In the self-locking zone. the tole
19、rances amlv lubrication, 2 Afore forming out-of-round. -3 *- ; CEN PREN*3?33 93 3404589 0030557 8 prEN 3713 Page 6 4 Designation Example : Description block Identity block Nut Diameter code (see table) J Note : If necessary, the originator code I9005 shall be placed between the description block and the identity block. 5 Marking EN 2424, style N. See figure. 6 Technical specification IS0 5858 except for : - approval of manufacturers : EN 2000 ; - qualification of products : EN 3042. _c? I -.
