1、BRITISH STANDARD AEROSPACE SERIES BS EN 4048:2004 Nuts, self-locking, MJ threads, in heat resisting nickel base alloy NI-PH2601 (Inconel 718), MoS 2coated Classification: 1 550 MPa (at ambient temperature) / 425 C Technical specification The European Standard EN 4048:2004 has the status of a British
2、 Standard ICS 49.030.30 BS EN 4048:2004 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 16 December 2004 BSI 16 December 2004 ISBN 0 580 45108 9 National foreword This British Standard is the official English language version of EN 4048:2004.
3、 It supersedes BS EN 4048:2003 which is withdrawn. The UK participation in its preparation was 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
4、secretary. Cross-references The British Standards which implement international or European 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 C
5、atalogue or of British Standards Online. This publication does not purport to include all the 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 understa
6、nd the text; present to the responsible international/European committee any enquiries on the 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
7、 front cover, an inside front cover, the EN title page, pages 2 to 18, an inside back cover 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 EUROPEAN STANDARD NORME EUROPENNE
8、EUROPISCHE NORM EN 4048 November 2004 ICS 49.030.30 Supersedes EN 4048:2003 English version Aerospace series - Nuts, self-locking, MJ threads, in heat resisting nickel base alloy NI-PH2601 (Inconel 718), MoS2 coated - Classification: 1 550 MPa (at ambient temperature) / 425 C - Technical specificati
9、on Srie arospatiale - crous, freinage interne, filetage MJ, en alliage rsistant chaud base de nickel NI- PH2601 (Inconel 718), revtus MoS2 - Classification : 1 550 MPa ( temprature ambiante) / 425 C - Spcification technique Luft- und Raumfahrt - Muttern, selbstsichernd, MJ- Gewinde, aus hochwarmfest
10、er Nickelbasislegierung NI- PH2601 (Inconel 718), MoS2-beschichtet - Klasse: 1 550 MPa (bei Raumtemperatur) / 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 stipulat
11、e the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exist
12、s in three official versions (English, French, German). A version in any other language made by translation under the responsibility of 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 bodi
13、es of Austria, Belgium, Cyprus, Czech 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. EUROPEAN COMMITTEE FOR
14、 STANDARDIZATION COMIT EUROPEN 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 4048:2004: EEN 4048:2004 (E) 2 Contents Page
15、 Foreword3 1 Scope4 2 Normative references4 3 Terms and definitions .4 4 Quality assurance6 4.1 Qualification.6 4.2 Acceptance.6 4.2.1 Purpose.6 4.2.2 Conditions7 4.2.3 Responsibility7 4.2.4 Inspection and test report.7 5 Requirements.8 EN 4048:2004 (E) 3 Foreword This document EN 4048:2004 has been
16、 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 approval of the National Associations and the Official Services of the member countr
17、ies 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 conflicting national standards shall be withdrawn at the latest by May 2005. This docu
18、ment supersedes EN 4048:2003. 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, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Icela
19、nd, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. EN 4048:2004 (E) 4 1 Scope This standard specifies the characteristics, qualification and acceptance requirements for self-locking n
20、uts with MJ threads in NI-PH2601, MoS 2coated, for aerospace applications. Classification: 1 550 MPa 1)/ 425 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 edit
21、ion cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 1463, Metallic and oxide coatings Measurement of coating thickness Microscopical method ISO 2859-1, Sampling procedures for inspection by attributes Part 1: Sampling schem
22、es 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) Surface texture: Profile method Rules and procedures for the assessment of surface texture ISO 5855-2, A
23、erospace MJ threads Part 2: Limit dimensions for bolts and nuts ISO 8642, Aerospace Self-locking nuts with maximum operating temperature greater than 425 C Test methods EN 2491, Aerospace series Molybdenum disulphide dry lubricants Coating methods EN 9133, Aerospace series Quality management systems
24、 Qualifiation Procedure for Aerospace Standard Parts 3)ASTM E112-96, Standard Test Methods for Determining Average Grain Size 4)3 Terms and definitions For the purposes of this standard, the following terms and definitions apply. 3.1 batch quantity of finished parts, of the same type and same diamet
25、er, 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 the relevant heat treatments and surface treatments 3.2 inspection lot quantity of parts from a single production
26、batch with the same part number which completely defines the part 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) Publish
27、ed as AECMA Prestandard 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 EN 4048:2004 (E) 5 3.3 Surface discontinuities 3.3.1 crack rupture in the material which may extend in any direction
28、and which may be intercrystalline or transcrystalline in character 3.3.2 seam 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 manufa
29、cturing process. These particles may be isolated or arranged in strings. 3.4 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
30、 of being chosen 3.6 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 likely to prevent performance of the function of a major end item
31、3.7 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 3.8 minor defect a defect that is not likely to reduce materially the usability of the considered product for its intended pur
32、pose, or that is a departure from established specification having little 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 )
33、 in a sampling plan, the quality limit which corresponds to a specified 10 % probability of acceptance 3.11 acceptance quality limit (AQL) a quality limit which in a sampling plan corresponds to a specified but relatively high probability of acceptance It is the maximum per cent defective (or the ma
34、ximum number of defects per hundred units) that, for purposes of sampling inspection can be considered satisfactory as a process average. EN 4048:2004 (E) 6 3.12 finished nut a nut ready for use, inclusive of any possible treatments and/or surface coatings, as specified in the product standard or de
35、finition 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 under no axial load and the nut locking s
36、ystem 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 the untightening torque to be applied to
37、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 axial load in the assembly has been removed
38、 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, methods, numbers of nuts) are specified in Tab
39、le 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. Any such decision shall be based on the resu
40、lts 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. 4.2 Acceptance 4.2.1 Purpose The purpose of acceptance inspections and tests is to check, as simply
41、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. EN 4048:2004 (E) 7 4.2.2 Conditions Acceptance inspections and tests (requirements, methods, number
42、s 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 tested shall be selected by simple random sampling. Each nut may be submitted to several inspections or tests. If a more stringent inspection is deemed necessar
43、y, 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 Responsibility Acceptance ins
44、pections 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. EN 4048:2004 (E) 8 5 Requirements See Table 1. Table 1 Technical requirements
45、 and test methods Clause Characteristic 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 43 5.2 Dimensions,
46、tolerances and tolerances of form and position In accordance with the product standard or definition document Standard gauging A Tables 3 and 4 5.3 Manufacturing The method of forming shall be indicated. Q 5.3.1 Forming Nuts shall be formed by a hot or cold forming process. If hot formed, the formin
47、g 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. Q 5.3.2 Heat treatment The heat treatment medium or atmosphere shall not cause any surface contamination except as permitted by 5.5.4. Cali
48、bration of the heat treatment equipment shall be confirmed. Any scale which will not be removed by subsequent machining shall be removed by abrasive blasting with an appropriate equipment. Visual examination Solution treat (if applicable) at a temperature of 950 C to 980 C, hold at the selected temp
49、erature within 15 C for between 1 h min. and 2 h max., quench in oil, or alternative medium or faster. Precipitation treatment at (720 5) C, held at temperature for 8 h 15 min, furnace cooled at (55 5) C per hour to (620 5) C, held at 620 C for 8 h 5 min, followed by air cooling or faster. Instead of the 55 C per hour cooling rate to 620 C, parts may be furnace cooled at any rate provided the time at 620 C is adj
