1、BRITISH STANDARD AEROSPACE SERIES BS EN 3004:1997 Nuts, self-locking, MJ threads, in heat resisting steel FE-PA2601 (A286) Classification: 1100MPa (at ambient temperature)/650C Technical specification The European Standard EN3004:1997 has the status of a British Standard ICS 49.040.20BSEN 3004:1997
2、This British Standard, having been prepared under the direction of the Engineering Sector Board, was published under the authority of the Standards Board and comes into effect on 15 June 1997 BSI 03-1999 The following BSI references relate to the work on this standard: Committee reference ACE/12 Dra
3、ft for comment 89/75236 DC ISBN 0 580 26689 3 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee ACE/12, Aerospace fasteners and fastening systems, upon which the following bodies were represented: British Industrial Fastene
4、rs Federation Ministry of Defence Society of British Aerospace Companies Amendments issued since publication Amd. No. Date CommentsBSEN 3004:1997 BSI 03-1999 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4
5、 Quality assurance 4 5 Requirements 5 Table 1 Technical requirements and test methods 6 Table 2 Allocation of qualification testing requirements 13 Table 3 Classification of defects 15 Table 4 Sampling plans for visual inspections and dimensional characteristics 15 Table 5 Minimum values for axial l
6、oad, wrench feature torque, push out load, torque out test and seating torque for vibration test 16 Table 6 Sampling plans for the inspection of mechanical and metallurgical characteristics 16 Table 7 Values of breakaway torque, self-locking torque and seating torque 17 Table 8 Permissible surface d
7、iscontinuities 17 List of references Inside back coverBSEN 3004:1997 ii BSI 03-1999 National foreword This British Standard has been prepared by Technical Committee ACE/12 and is the English language version of EN3004:1997 Aerospace series Nuts, self-locking, MJ threads, in heat resisting steel FE-P
8、A2601 (A286) Classification: 1100MPa (at ambient temperature)/650C Technical specification, published by the European Committee for Standardization (CEN). EN 3004:1997 was produced as a result of international discussions in which the United Kingdom took an active part. A British Standard does not p
9、urport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references Publication referred to Corresponding British Standar
10、d EN 3042:1991 BS EN 3042:1992 Quality assurance. EN aerospace products. Qualification procedure BS 6001 Sampling procedures for inspection by attributes ISO 2859-1:1991 Part 1:1991 Specification for sampling plans indexed by acceptable quality level (AQL) for lot-by-lot inspection ISO 8642:1986 BS
11、A 298:1988 Method of test for self-locking nuts with maximum operating temperature greater than425C Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2 to 18, an inside back cover and a back cover. This standard has been updated (s
12、ee copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 3004 January 1997 ICS 49.040.20 Descriptors: Aircraft industry, nut, fastener, self-locking nut, steel, heat resist
13、ant steel, classification, quality assurance, specification, characteristic, inspection, test English version Aerospace series Nuts, self-locking, MJ threads, in heat resisting steel FE-PA2601 (A286) Classification: 1100MPa (at ambient temperature)/650C Technical specification Srie arospatiale Ecrou
14、s, freinage interne, filetage MJ, en acier rsistant chaud FE-PA2601 (A286) Classification: 1 100 MPa ( temprature ambiante)/650C Spcification technique Luft-und Raumfahrt Muttern, selbstsichernd, MJ-Gewinde, aus hochwarmfestem Stahl FE-PA2601 (A286) Klasse: 1100MPa (bei Raumtemperatur)/650 C Technis
15、che Lieferbedingungen This European Standard was approved by CEN on1996-10-27. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bib
16、liographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. The European Standards exist in three official versions (English, French, German). A version in any other language made by translation under the responsibility o
17、f a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal,
18、 Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1997 Copyright reserved to CEN members Ref. No. EN3004:1997 EEN3004:1997 BSI 03-1999 2 For
19、eword This European Standard has been prepared by the European Association of Aerospace Manufacturers (AECMA). After inquiries and votes carried out in accordance with the rules of this Association, this Standard has received the approval of the National Associations and the Official Services of the
20、 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 byJuly1997, and conflicting national standards shall be withdrawn at the latest byJuly199
21、7. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain,
22、 Sweden, Switzerland and the United Kingdom.EN3004:1997 BSI 03-1999 3 1 Scope This standard specifies the characteristics, qualification and acceptance requirements for self-locking nuts with MJ threads in FE-PA2601. Classification: 1100MPa 1) /650C 2) . It is applicable whenever referenced. 2 Norma
23、tive references This European Standard incorporates by dated or undated reference provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of a
24、ny of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. ISO 2859-1, Sampling procedures for inspection by attributes Part 1: Sampling plans indexed by acceptable
25、quality level (AQL) for lot-by-lot inspection. ISO 3452, Non-destructive testing Penetrant inspection General principles. ISO 3534-1977, Statistics Vocabulary and symbols. ISO 4288, Rules and procedures for the measurement of surface roughness using stylus instruments. ISO 8642, Aerospace Self-locki
26、ng nuts with maximum operating temperature greater than425C Test methods. EN 2786, Aerospace series Electrolytic silver plating of fasteners 3) . EN 3042, Aerospace Series Quality assurance EN aerospace products Qualification procedure. ASTM E 112-88, Standard Test Methods for Determining Average Gr
27、ain Size 4) . 3 Definitions For the purposes of this standard, the following definitions apply: 3.1 batch quantity of finished nuts, of the same type and same diameter, produced from a material obtained from the same melt, manufactured in the course of the same production cycle, following the same m
28、anufacturing route and having undergone all the relevant heat treatments and surface treatments 3.2 Surface discontinuities 3.2.1 crack rupture in the material which may extend in any direction and which may be intercrystalline or transcrystalline in character 3.2.2 seam open surface defect 3.2.3 la
29、p surface defect caused by folding over metal fins or sharp corners and then compressing them into the surface 3.2.4 inclusions non-metallic particles originating from the material manufacturing process. These particles may be isolated or arranged in strings 3.3 test temperature ambient temperature,
30、 unless otherwise specified 3.4 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 5) 1) Corresponds to the minimum tensile stress which the nut is able to withstand at ambient te
31、mperature 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 Prestandard at the date of publication of this standard 4) Published by : American Society for Testing and Materials (ASTM), 1916, Race Street, Ph
32、iladelphia, PA 19103, USA 5) Definition taken from ISO3534EN3004:1997 4 BSI 03-1999 3.5 critical defect a defect that, according to judgement and experience, is likely to result in hazardous or unsafe conditions for individuals using, maintaining, or depending upon the considered product, or that is
33、 likely to prevent performance of the function of a major end item 5) 3.6 major defect a defect other than critical, that is likely to result in a failure or to reduce materially the usability of the considered product for its intended purpose 5) 3.7 minor defect a defect that is not likely to reduc
34、e materially the usability of the considered product for its intended purpose, or that is a departure from established specification having little bearing on the effective use or operation of this product 5) 3.8 sampling plan a plan according to which one or more samples are taken in order to obtain
35、 information and possibly to reach a decision 5) 3.9 limiting quality in a sampling plan, the quality level which corresponds to the specified10% probability of acceptance 3.10 acceptable quality level (AQL) a quality level which in a sampling plan corresponds to a specified but relatively high prob
36、ability 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 5) 3.11 finished nut a nut ready for use, inclusive of any possible treatments and/or surface
37、coatings, as specified in the product standard or definition document 3.12 definition document document specifying all the requirements for finished nuts 3.13 self-locking torque the torque to be applied to the nut or bolt to maintain its movement of rotation in relation to the associated part, the
38、assembly being under no axial load and the nut locking zone being completely engaged with the bolt (minimum protrusion of two pitches, including the end chamfer) 3.14 seating torque the tightening torque to be applied to the nut or bolt to introduce or to increase the axial load in the assembly 3.15
39、 unseating torque the untightening torque to be applied to the nut or bolt to reduce or remove the axial load in the assembly 3.16 breakaway torque the torque required to start unscrewing the nut or bolt with respect to the associated part, with the nut locking zone still fully engaged on the bolt,
40、but after the axial load in the assembly has been removed by unscrewing half a turn followed by a halt in rotational movement 3.17 torque for testing the wrench feature the torque to be applied to the wrenching feature of the nut 4 Quality assurance 4.1 Qualification EN 3042 Qualification inspection
41、s and tests (requirements, methods, 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 batch by simple random sampling. The test programme may possibly be reduced, or the qualification be granted without inspection o
42、r testing: any 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 sample for the inspections and tests.EN3004:1997 BSI 03-1999 5 4.2 Acceptance 4.2.1
43、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, that the nuts constituting the batch satisfy the requirements of this standard. 4.2.2 Conditions Acc
44、eptance inspections and tests (requirements, methods, numbers of nuts) are specified inTable 1. They shall be carried out on each batch. Nuts from the batch to be tested shall be selected by simple random sampling. Each nut may be submitted to several inspections or tests. If a more stringent inspec
45、tion 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 number of nuts submitted to these inspections and tests is the same as that submitted for qualification inspection and tests. 4.2.3 Respon
46、sibility 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 showing actual numerical values shall be provided if specified in the purchase order. 5 Requirements SeeTable 1.EN3004:1997 6 BSI 03-1999 Ta
47、ble 1 Technical requirements and test methods Clause Characteristic Requirement Inspection and test method Q/A a Sample size 5.1 Material In accordance with the product standard or definition document Chemical analysis or certificate of compliance issued by the manufacturer of the semi-finished prod
48、uct Q A 5.2 Dimensions, tolerances and tolerances of form and position In accordance with the product standard or definition document Standard gauging Q 46 A Table 3 andTable 4 5.3 Manufacturing 5.3.1 Forming Nuts shall be formed by a hot or cold forming process. The method of forming shall be indic
49、ated. Q If hot formed, the forming temperature shall not exceed1150C and they shall be air cooled or faster. The equipment shall ensure a uniform temperature throughout the batch. 5.3.2 Heat treatment The heat treatment medium or atmosphere shall not cause any surface contamination except as permitted by5.5.4. Calibration of the heat treatment equipment shall be confirmed. Q Any scale which will not be removed by subsequent machining shall be removed by abrasive blasting with an a
