1、Licensed Copy: Wang Bin, ISO/Exchange China Standards Information Centre, 04 April 2005, Uncontrolled Copy, (c) BSIBRITISH STANDARD AEROSPACE SERIES BS EN 3752:2004 Nuts, self-locking, MJ threads, in heat resisting steel FE-PA2601 (A286), MoS 2 coated Classification: 1 100 MPa (at ambient temperatur
2、e) / 425 C Technical specification The European Standard EN 3752:2004 has the status of a British Standard ICS 49.030.30 Licensed Copy: Wang Bin, ISO/Exchange China Standards Information Centre, 04 April 2005, Uncontrolled Copy, (c) BSIBS EN 3752:2004 This British Standard was published under the au
3、thority of the Standards Policy and Strategy Committee on 5 January 2005 BSI 5 January 2005 ISBN 0 580 45184 4 National foreword This British Standard is the official English language version of EN 3752:2004. It supersedes BS EN 3752:2003 which is withdrawn. The UK participation in its preparation w
4、as entrusted to Technical Committee ACE/12, Aerospace fasteners and fastening systems, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European
5、publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all th
6、e necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on th
7、e interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 18, an inside back cover
8、and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments Licensed Copy: Wang Bin, ISO/Exchange China Standards Information Centre, 04 April 2005, Uncontrolled Copy, (c) BSI EUROPEAN S
9、TANDARD NORME EUROPENNE EUROPISCHE NORM EN 3752 November 2004 ICS 49.030.30 Supersedes EN 3752:2003 English version Aerospace series - Nuts, self- locking, MJ threads, in heat resisting steel FE-PA2601 (A286), MoS 2 coated - Classification: 1 100 MPa (at ambient temperature) / 425 C - Technical spec
10、ification Srie arospatiale - crous, freinage interne, filetage MJ, en acier rsistant chaud FE-PA2601 ( A286 ) , revtus MoS2 - Classification : 1 100 MPa ( temprature ambiante ) / 425 C - Spcification technique Luft- und Raumfahrt - Muttern, selbstsichernd, MJ-Gewinde, aus hochwarmfestem Stahl FE-PA2
11、601 (A286), MoS2- beschichtet - Klasse: 1 100 MPa ( bei Raumtem p eratur ) / 425 C - Technische Lieferbedingungen This European Standard was approved by CEN on 11 September 2003. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
12、Europe an Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning s uch national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (E
13、nglish, French, German). A version in any other language made by tra nslation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the off icial versions. CEN members are the national standards bodies of Austria, Belgium, Cypru
14、s, Czech Republic, Denmark, Estonia, Finland, France, G ermany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia , Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EURO
15、PEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2004 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 3752:2004: E Licensed Copy: Wang Bin, ISO/Exchange China Standards Info
16、rmation Centre, 04 April 2005, Uncontrolled Copy, (c) BSI EN 3752:2004 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Quality assurance6 5 Requirements.7 Licensed Copy: Wang Bin, ISO/Exchange China Standards Information Centre, 04 April 2005, Uncontroll
17、ed Copy, (c) BSIEN 3752:2004 (E) 3 Foreword This document (EN 3752:2004) has been prepared by the European Association of Aerospace Manufacturers - Standardization (AECMA-STAN). After enquiries and votes carried out in accordance with the rules of this Association, this Standard has received the app
18、roval of the National Associations and the Official Services of the member countries of AECMA, prior to its presentation to CEN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2005, and confl
19、icting national standards shall be withdrawn at the latest by May 2005. This document supersedes EN 3752:2003. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, C
20、zech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: Wang Bin, ISO/Exchange China Standards I
21、nformation Centre, 04 April 2005, Uncontrolled Copy, (c) BSI EN 3752:2004 (E) 4 1 Scope This standard specifies the characteristics; qualification and acceptance requirements for self-locking nuts with MJ threads in FE-PA2601, MoS 2coated, for aerospace applications. Classification: 1 100 MPa 1)/ 42
22、5 C 2)It is applicable whenever referenced. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any ame
23、ndments) applies. ISO 2859-1, Sampling procedures for inspection by attributes Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection ISO 3452, Non-destructive testing Penetrant inspection General principles ISO 4288, Geometrical Product Specifications (GPS) Sur
24、face texture: Profile method Rules and procedures for the assessment of surface texture ISO 5855-2, Aerospace MJ threads Part 2: Limit dimensions for bolts and nuts ISO 7481, Aerospace Nuts, self-locking, with maximum operating temperature less than or equal to 425 C Test methods EN 2491, Aerospace
25、series Molybdenum disulphide dry lubricants Coating methods EN 9133, Aerospace series Quality management systems Qualification procedure for aerospace standard parts 3)ASTM E 112-96, Standard Test Methods for Determining Average Grain Size 4)3 Terms and definitions For the purposes of this standard,
26、 the following terms and definitions apply. 3.1 batch quantity of finished nuts, of the same type and same diameter, produced from the same material obtained from the same melt, manufactured in the course of the same production cycle, following the same manufacturing route and having undergone all t
27、he relevant heat treatments and surface treatments 1) Correspond 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 test temperature of the parts 3) Published as AECMA Pre
28、standard at the date of publication of this standard 4) Published by: American Society for Testing and Materials (ASTM), 1916, Race Street, Philadelphia, PA 19103, USA Licensed Copy: Wang Bin, ISO/Exchange China Standards Information Centre, 04 April 2005, Uncontrolled Copy, (c) BSIEN 3752:2004 (E)
29、5 3.2 inspection lot quantity of nuts from a single production batch with the same part number which completely defines the nut 3.3 Surface discontinuities 3.3.1 crack rupture in the material which may extend in any direction and which may be intercrystalline or transcrystalline in character 3.3.2 s
30、eam open surface defect 3.3.3 lap surface defect caused by folding over metal fins or sharp corners and then rolling or forging them into the surface 3.3.4 inclusions non-metallic particles originating from the material manufacturing process. These particles may be isolated or arranged in strings. 3
31、.4 test temperature ambient temperature unless otherwise specified 3.5 simple random sampling the taking of n items from a population of N items in such a way that all possible combinations of n items have the same probability of being chosen 3.6 critical defect a defect that, according to judgement
32、 and experience, is likely to result in hazardous or unsafe conditions for individuals using, maintaining, or depending upon the considered product, or that is likely to prevent performance of the function of a major end item 3.7 major defect a defect other than critical, that is likely to result in
33、 a failure or to reduce materially the usability of the considered product for its intended purpose 3.8 minor defect a defect that is not likely to reduce materially the usability of the considered product for its intended purpose, or that is a departure from established specification having little
34、bearing on the effective use or operation of this product 3.9 sampling plan a plan according to which one or more samples are taken in order to obtain information and possibly to reach a decision 3.10 limiting quality (LQ 10 ) in a sampling plan, the quality limit which corresponds to a specified 10
35、 % probability of acceptance Licensed Copy: Wang Bin, ISO/Exchange China Standards Information Centre, 04 April 2005, Uncontrolled Copy, (c) BSI EN 3752:2004 (E) 6 3.11 acceptance quality limit (AQL) a quality limit which in a sampling plan corresponds to a specified but relatively high probability
36、of acceptance It is the maximum per cent defective (or the maximum number of defects per hundred units) that, for purposes of sampling inspection can be considered satisfactory as a process average. 3.12 finished nut a nut ready for use, inclusive of any possible treatments and/or surface coatings,
37、as specified in the product standard or definition document 3.13 definition document document specifying all the requirements for finished nuts 3.14 self-locking torque the torque to be applied to the nut or bolt to maintain movement of rotation in relation to the associated part, the assembly being
38、 under no axial load and the nut locking system being completely engaged with the bolt (minimum protrusion of two pitches including end chamfer) 3.15 seating torque the tightening torque to be applied to the nut or bolt to introduce or to increase the axial load in the assembly 3.16 unseating torque
39、 the untightening torque to be applied to the nut or bolt to reduce or remove the axial load in the assembly 3.17 breakaway torque the torque required to start unscrewing the nut or bolt with respect to the associated part, with the nut locking device still fully engaged on the bolt, but after the a
40、xial load in the assembly has been removed by unscrewing half a turn followed by a halt in rotational movement 3.18 wrench feature torque the torque to be applied to the wrenching feature of the nut 4 Quality assurance 4.1 Qualification EN 9133 Qualification inspections and tests (requirements, meth
41、ods, numbers of nuts) are specified in Table 1. They shall be carried out on: each type and diameter of nut; 46 nuts selected from a single inspection lot by simple random sampling. The test programme may possibly be reduced, or the qualification of a nut be granted without inspection or testing. An
42、y such decision shall be based on the results obtained on similar types and diameters of nuts provided that the design and manufacturing conditions are identical. Table 2 indicates the allocation of nut samples for the inspections and tests. Licensed Copy: Wang Bin, ISO/Exchange China Standards Info
43、rmation Centre, 04 April 2005, Uncontrolled Copy, (c) BSIEN 3752:2004 (E) 7 4.2 Acceptance 4.2.1 Purpose The purpose of acceptance inspections and tests is to check, as simply as possible, by a method representative of actual use conditions, with the uncertainty inherent to statistical sampling, tha
44、t the nuts constituting the batch satisfy the requirements of this standard. 4.2.2 Conditions Acceptance inspections and tests (requirements, methods, numbers of nuts) are specified in table 1 ; they shall be carried out on each production batch or inspection lot. Nuts from the batch or lot to be te
45、sted shall be selected by simple random sampling. Each nut may be submitted to several inspections or tests. If a more stringent inspection is deemed necessary, all or part of the qualification inspections and tests may be performed during the acceptance inspection and testing. In this case, the num
46、ber of nuts submitted to these inspections and tests is the same as that submitted for qualification inspection and tests. 4.2.3 Responsibility Acceptance inspections and tests shall be carried out by the manufacturer, or under his responsibility. 4.2.4 Inspection and test report A test report showi
47、ng actual numerical values shall be provided if specified in the purchase order. 5 Requirements See Table 1. Licensed Copy: Wang Bin, ISO/Exchange China Standards Information Centre, 04 April 2005, Uncontrolled Copy, (c) BSI EN 3752:2004 (E) 8 Table 1 Technical requirements and test methods Clause C
48、haracteristic Requirement Inspection and test method Q/A aSample size Q 5.1 Material In accordance with the product standard or definition document Chemical analysis or certificate of conformity issued by the manufacturer of the semi-finished product A Q 46 5.2 Dimensions, tolerances and tolerances
49、of form and position In accordance with the product standard or definition document Standard gauging A Tables 3 and 4 5.3 Manufacturing Q 5.3.1 Forming Nuts shall be formed by a hot or cold forming process. If hot formed, the forming temperature shall not exceed 1 150 C and they shall be air cooled or faster. The equipment shall ensure a uniform temperature throughout the production batch. The method of forming shall be indicated. Q The h
