1、BRITISH STANDARD AEROSPACE SERIES BS EN 3676:1998 Inserts, thin wall, self-locking Design standard The European Standard EN3676:1998 has the status of a British Standard ICS 49.030.30BSEN 3676:1998 This British Standard, having been prepared under the directionof the Engineering SectorBoard, was pub
2、lished underthe authority of the Standards Board and comes intoeffect on 15 May 1998 BSI 04-1999 ISBN 0 580 29757 8 National foreword This British Standard is the English language version of EN3676:1998. The UK participation in its preparation was entrusted by Technical Committee ACE/12, Aerospace f
3、asteners and fastening systems, to Subcommittee ACE/12/1, Aerospace fasteners and fastening systems (international), which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals fo
4、r change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement internatio
5、nal or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include a
6、ll 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. Summary of pages This document comprises a front cover, an inside front cover, pages i an
7、d ii, theEN title page, pages 2 to 10 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSEN 3676:1998 BSI
8、04-1999 i Contents Page National foreword Inside front cover Foreword 2 Text of EN 3676 3ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 3676 January 1998 ICS 49.030.99 Descriptors: Aircraft industry, joining adaptor, specification, design, utilization, characteristic, dimension, hole s
9、ize, designation English version Aerospace series Inserts, thin wall, self-locking Design standard Srie arospatiale Douilles filetes, paroi mince, freinage interne Norme de conception Luff-und Raumfahrt Gewindeeinstze, dnnwandig, selbstsichernd Konstruktionsnorm This European Standard was approved b
10、y CEN on 18 September 1997. 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 bibliographical references concerning such national st
11、andards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists 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
12、to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and Uni
13、ted Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1998 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 367
14、6:1998 EEN 3676:1998 BSI 04-1999 2 Foreword 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 successively received the approval of the Nat
15、ional 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 July 1998, and conflicting national
16、 standards shall be withdrawn at the latest by July 1998. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Icel
17、and, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Design 3 4 Use 4 5 Required characteristics 5 6 Installation 8 7 Provisions for component salvage 8 8 Designation 9 Figure
18、1 3 Figure 2 3 Figure 3 4 Figure 4 5 Figure 5 6 Figure 6 7 Figure 7 8 Figure 8 9 Figure 9 10 Figure 10 10 Figure 11 10 Table 1 4 Table 2 5 Table 3 5 Table 4 6 Table 5 8 Table 6 9EN 3676:1998 BSI 04-1999 3 1 Scope This standard specifies the use and installation hole dimensions for EN standard, self-
19、locking, thin wall inserts, for aerospace applications and provisions for component salvage. 2 Normative 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
20、 publications are listed hereafter. For dated references, subsequent amendments to or revisions of any 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 58
21、55-1, Aerospace MJ threads Part 1: General requirements. ISO 5855-2, Aerospace MJ threads Part 2: Limit dimensions for bolts and nuts. EN 3236, Aerospace series Inserts, thin wall, self-locking, short, in heat resisting nickel base alloy NI-P100HT (Inconel 718), silver plated internal thread 1) . EN
22、 3237, Aerospace series Inserts, thin wall, self-locking, long, in heat resisting nickel base alloy NI-P100HT (Inconel 718), silver plated internal thread 1) . EN 3298, Aerospace series Inserts, thin wall, self-locking Installation and removal procedure 1) . EN 3916, Aerospace series Inserts, thin w
23、all, self-locking Non-conformance procedure for components using salvage 2) . 3 Design Typical examples of installed inserts are illustrated in Figure 1 and Figure 2. There are two lengths of inserts, a short one and a long one (selection being dependent on application), each having its own part num
24、ber range as given inTable 1. 1) Published as AECMA Prestandard at the date of publication of this standard 2) In preparation at the date of publication of this standard Figure 1 Figure 2 EN 3676:1998 4 BSI 04-1999 Table 1 The minimum flange thickness “F” given inTable 4 is less than the insert leng
25、ths given inTable 1. When using these minimum flange thicknesses, protrusion of the insert will occur. Designers shall therefore ensure that the insert does not protrude into an abutment face or foul any other adjacent features. The minimum flange thickness has been calculated to provide sufficient
26、insert thread engagement, to ensure the insert does not creep, when the associated bolt is tightened. 4 Use 4.1 General A self-locking thin wall insert as shown inFigure 3 is a sleeve of metal which is threaded both internally and externally, with an externally serrated upper portion. These inserts
27、are screwed into tapped holes which contain counterbores (see5.1) and are fixed by swaging the serrated portion into the counterbore of the component (seeFigure 1 and Figure 2) thus preventing the insert moving during the installation or removal of a bolt. The self-locking zone of these inserts is p
28、ositioned at the mid point approximately of the internal threaded portion. These inserts shall be silver plated only on their internal thread. Inserts may be used: in blind and open ended tapped holes; in various types of materials ranging from light alloys to corrosion and heat resisting steels, ni
29、ckel and titanium alloys. The installed insert is suitable for use with bolts with MJ threads to ISO5855-1. Short inserts to EN3236 are used in hard materials such as steel, nickel and titanium alloys and are installed into a tapped hole which contains a serrated counterbore, see5.2. Long inserts to
30、 EN3237 are used in softer materials such as light alloys and are installed into a tapped hole with a plain counterbore. Dimensions in millimetres Associated bolt thread Short inserts Long inserts Part number Length 0,3 Part number Length 0,3 MJ50,8 EN 3236-050 7,6 EN 3237-050 13,15 MJ61 EN 3236-060
31、 8,9 EN 3237-060 15,35 MJ71 EN 3236-070 10,9 EN 3237-070 17,75 MJ81 EN 3236-080 12,8 EN 3237-080 20,15 MJ101,25 EN 3236-100 16,2 EN 3237-100 24,85 Figure 3 EN 3676:1998 BSI 04-1999 5 4.2 Performance and material The inserts toTable 1 have a minimum performance of25 re-uses at the maximum test temper
32、ature of550C. It should be noted that there will be a progressive increase in the insert re-usability when used at lower temperatures. The self-locking torque values for these inserts are given inTable 2. NOTETemperature limitations may depend on the material into which an insert has been installed.
33、 Table 2 4.3 Installation restrictions In applications where it is necessary to pass items through the installed insert, care shall be taken to ensure that such items do not foul the locking feature of the insert. The maximum diameter X that can be passed through the insert is illustrated inFigure 4
34、 and dimensions are given inTable 3. Table 3 5 Required characteristics SeeFigure 5 andTable 4. 5.1 Installation hole The plain counterbore depth “D” 1applies when inserts are to be installed into light alloy components. The serrated counterbore “D 2 ” applies when inserts are to be installed into h
35、ard materials, see4.1. Dimension “E” is the recommended minimum boss thickness. Designers shall select boss thickness based on the methods of manufacture of the component (e.g.casting, forging or fully machined). Associated bolt thread Self-locking torque Nm mm max. min. MJ5O,8 2,5 0,25 MJ61 3,2 0,3
36、5 MJ71 4,6 0,50 MJ81 6,0 0,65 MJ101 ,25 9,5 1,20 Dimensions in millimetres Associated bolt thread X max. MJ50,8 3,12 MJ61 3,70 MJ71 4,50 MJ81 5,30 MJ101,25 6,64 Figure 4 EN 3676:1998 6 BSI 04-1999 For provisions for salvage, see7. Table 4 Figure 5 Dimensions in millimetres Hole Associated bolt threa
37、d Thread diameter b B c C D 1 D 2 Diameter code Length code a max. min. max. min. max. min. max. min. 050 L MJ50,8 MJ71-4H5H (MOD) 6,13 6,03 7,1 7,0 2,65 2,4 S 3,05 2,8 060 L MJ61 MJ81-4H5H (MOD) 7,17 7,07 8,1 8,0 2,75 2,5 S 3,15 2,9 070 L MJ71 MJ91-4H5H (MOD) 8,20 8,10 9,1 9,0 3,05 2,8 S 3,45 3,2 0
38、80 L MJ81 MJ101-4H5H (MOD) 9,24 9,11 10,1 10,0 3,25 3,0 S 3,65 3,4 100 L MJ101,25 MJ121-4H5H (MOD) 11,29 11,16 12,1 12,0 3,65 3,4 S 4,05 3,8EN 3676:1998 BSI 04-1999 7 Table 4 5.2 Serrations Figure 6 and Table 5 provide the information required to produce the serration in the counterbore. The serrati
39、on profiles are produced to EN3298, using a special broaching tool (Wobble broach) with the cutting tool offset by1 to the broaching tool body. Sufficient space shall be provided around each hole to allow access for the broaching tool, seeFigure 7. Hole Associated bolt thread E F d G e H e M N e R 1
40、 Diameter code Length code a min. min. min. max. max. min. min. max. 050 L MJ50,8 6,5 13,0 14,15 19,6 8,5 8,2 S 5,5 7,3 8,6 14,05 060 L MJ61 7,0 15,5 16,35 21,8 9,5 9,2 S 6,0 8,6 9,9 15,35 070 L MJ71 7,5 18,0 18,75 24,2 10,5 10,2 2,0 0,25 S 6,5 10,6 11,9 17,35 080 L MJ81 8,0 20,0 21,15 26,6 11,5 11,
41、2 S 7,0 12,5 13,8 19,25 100 L MJ101,25 9,0 25,0 25,85 31,3 13,5 13,2 S 8,0 15,9 17,2 22,65 a Length code L for long inserts (EN3237), code S for short inserts (EN3236) b In accordance with ISO5855-2, except modified minor diameter c Modified minor diameter d Open ended tapped holes e Blind tapped ho
42、les Figure 6 EN 3676:1998 8 BSI 04-1999 Table 5 6 Installation EN3298 Inserts shall be installed between0,4mm and0,65mm below the surface of the component. 7 Provisions for component salvage When inserts are selected for a design, consideration shall be given to the feasibility of component salvage
43、where the original hole could be damaged during manufacture, or where the hole is machined out of position. Before provision is made for component salvage, consideration shall be given to component cost/mass requirements, e.g.for an inexpensive component salvage may not be an economic proposition, w
44、hereas an expensive component may necessitate salvage. Where provision for salvage is made, the component will be heavier because of the increase in wall thickness around the tapped holes. If a decision for component salvage was made, the minimum boss thickness “S 1 ” and “S 2 ” inTable 6 andFigure
45、8 shall be used instead of dimension E inTable 4. In the event of component salvage action, hole preparation, salvage insert selection and installation shall be in accordance with EN3916. Dimensions in millimetres Hole K a j a R 2 a Diameter code Length code max. min. Number of serrations max. 050 2
46、65 2,02 18 060 2,75 2,12 24 070 S 3,05 2,42 27 0,25 080 3,25 2,62 28 100 3,65 3,02 33 a See EN3298. Figure 7 EN 3676:1998 BSI 04-1999 9 Table 6 8 Designation 8.1 Example 8.2 Installation hole for long inserts to EN3237 in soft materials (plain counterbore) EXAMPLE: seeFigure 9. Dimensions in millim
47、etres Associated bolt thread Boss thickness for component salvage Hole thread for component salvage a Long inserts Short inserts S 1min. S 2min. MJ50, 8 7,5 6,5 MJ91-4H5H MJ61 8,0 7,0 MJ101-4H5H MJ71 8,5 7,5 MJ111-4H5H MJ81 9,0 8,0 MJ121-4H5H MJ101,25 10,0 9,0 MJ141-4H5H a See EN3916. Figure 8 EN 36
48、76:1998 10 BSI 04-1999 Alternatively, the hole may be fully dimensioned on the drawing. 8.3 Installation hole for short inserts to EN3236 in hard materials (serrated counterbore) EXAMPLE: seeFigure 10. Alternatively, the hole may be fully dimensioned on the drawing. 8.4 Installed insert EXAMPLE: see
49、Figure 11. Figure 9 Figure 10 Figure 11 11 blankBS EN 3676:1998 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandards are updated by amendment or revision. Users of BritishStandards should make sure that they possess the latest
