1、STD-AECMA PREN 3757-ENGL 1778 m LOL23LL 001475b LO2 m Edition approved for publication AECMA STANDARD NORME AECMA AECMA NORM Comments should be sent within six months C3 Chairman after the date of publication to prEN 3757 Edition P 2 August 1998 PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE IND
2、USTRIES (AECMA) Gulledelle 94 - B-1200 BRUXELLES - Tel. (+32) 2 775 81 1 O - Fax. +32) 2 775 81 11 ICs: 49.040.20 Descriptors: Supersedes edition P 1 February 1993 and corrigendum No. 1 May 1993 ENGLISH VERSION Aerospace series Nuts, anchor, self-locking, floating, self-aligning, two lug, in heat re
3、sisting steel, Mos2 lubricated Classification: 900 MPa (at ambient temperature) / 315 OC Srie arospatiale Luft- und Raumfahrt crous river, freinage interne, flottants, orientables, double patte, en acier rsistant chaud, lubrifis Mos2 Classification: 900 MPa ( temprature ambiante) / 31 5 OC Annietmut
4、tern, selbstsichernd, schwenkbar, beiderseitiger Flansch, aus hochwarmfestem Stahl, MoS2-geschmiert Klasse: 900 MPa (bei Raumtemperatur) / 31 5 OC This “Aerospace Series“ Prestandard has been drawn up under the responsibility of AECMA (The European Association of Aerospace Industries). It is publish
5、ed 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 extent that interchang
6、eability 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 Services of the Member countries it will be submitted as a draft European Standard to CEN (Eur
7、opean Committee for Standardization) for formal vote. 1998-08-31 AECMA Gulledelle 94 I B-1200 BRUXELLES Mr Visconti aecma 199f COPYRIGHT Association Europeene Des Constructeurs de Materiel AerospaceLicensed by Information Handling ServicesSTD-AECMA PREN 3757-ENGL 3778 I 1012333 0034752 5b7 U Page 3
8、prEN 3757: 1998 I Scope This standard specifies the characteristics of self-locking, floating, self-aligning, two lug anchor nuts, in heat resisting steel, MoS2-lubricated. Classification: 900 MPa 1) / 315 OC 2) 2 Normative references IS0 5855-2 IS0 5858 IS0 8788 IS0 12273 EN 2000 EN 2424 EN 2491 EN
9、 3042 TR 3791 Aerospace - MJ threads - Part 2: Limit dimensions for bolts and nuts Aerospace - Self-locking nuts with maximum operating temperature less than or equal to 425 OC - Procurement specification Aerospace - Fasteners - Tolerances of form and position for nuts Aerospace - Nuts, anchor, self
10、-locking, floating, self-aligning, two lug, with MJ threads - Classification: 900 MPa (at ambient temperature) / 235 OC, 900 MPa (at ambient temperature) / 315 OC, 900 MPa (at ambient temperature) / 425 OC - Dimensions Aerospace series - Quality assurance - EN aerospace products - Approval of the qa
11、ality system of manufacturers Aerospace series - Marking of aerospace products Aerospace series - Molybdenum disulphide dry lubricants - Coating methods Aerospace series - Quality assurance - EN aerospace products - Qualification procedure Aerospace series - Materials for self-locking nuts, threaded
12、 inserts and screw thread inserts of temperature classes I425 OC 3) 1) Corresponds to the minimum tensile stress which the nut is able to withstand 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 wi
13、thstand, without permanent alteration to its original characteristics, after ambient temperature has been restored. The maximum temperature is conditioned by the surface treatment. 3) Published as AECMA Technical Report at the date of publication of this standard COPYRIGHT Association Europeene Des
14、Constructeurs de Materiel AerospaceLicensed by Information Handling ServicesPage 4 prEN 3757: 1998 3 Required characteristics 3.1 See figure 1 and table 1. Configuration - Dimensions - Masses Dimensions and tolerances are in conformity with IS0 12273, expressed in millimetres and apply before Mos2 l
15、ubrication. Details of form not stated are at the manufacturers option. 3.2 IS0 8788 Tolerances of form and position 3.3 Materials TR 3791 3.4 Surface treatment EN 2491, thickness not specified, mandatory on threads, optional on other surfaces COPYRIGHT Association Europeene Des Constructeurs de Mat
16、eriel AerospaceLicensed by Information Handling ServicesSTDmAECMA PREN 3757-ENGL 1778 I 1OL231L UOL4754 33T Diameter code 050 060 080 Remove sharp edges 0,l to 0,4. Thread 1) E F H K L M N2) P R S T Z Mass 3) Radial float min. max. max. max. max. min. - O max. min. + 0,2 N MJ50,8-4H6H 8.75 17,5 3,5
17、15,2 23,7 8,3 6,6 7.2 0,7 2,6 MJ6xl-4H5H 4 17 31,6 10,2 7,6 7,8 5,8 MJ8xl-4H5H 5 20,532,611,8 1.1 11 3,5 3 8.4 9 0,9 3 2,5 12,7 25,4 0,75 K Float inclusive I Page 5 prEN 3757: 1998 Y-Y J+ N+l ,- Convex washer Threaded element the self-locking torque requirement 31, LMI 1) These values in micrometres
18、 apply before 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) 8O minimum alignment in any direction from central position 3) Tooling marks are permitted in this area. Figure 1 COPYRIG
19、HT Association Europeene Des Constructeurs de Materiel AerospaceLicensed by Information Handling Services _ STD-AECMA PREN 3757-ENGL 1998 = LOL231L OOLi755 27b Page 6 prEN 3757: 1998 4 Designation EXAMPLE: Description block Identity block EN3757-060 Number of this standard Diameter code (see table 1
20、1 NOTE: If necessary, the code 19005 shall be placed between the description block and the identity block. 5 Marking EN 2424, style N. See 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 AerospaceLicensed by Information Handling Services
