hongbaoshu net BRITISH STANDARD BS EN 20273 1992 ISO 273 1979 Fasteners — Clearance holes for bolts and screws The European Standard EN 20273 1991 has the status of a British Standard NO COPYING WITHO[.]
BRITISH STANDARD Fasteners — Clearance holes for bolts and screws The European Standard EN 20273:1991 has the status of a British Standard NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BS EN 20273: 1992 ISO 273:1979 BS EN 20273:1992 Cooperating organizations The European Committee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries Austria Oesterreichisches Normungsinstitut Belgium Institut beige de normalisation Denmark Dansk Standardiseringsraad Finland Suomen Standardisoimisliito, r.y France Association frangaise de normalisation Germany Deutsches Institut fiir Normung e.V Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standards Authority of Ireland Italy Ente Nazionale Italiano di Unificazione Luxembourg Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugues da Qualidade Spain Asociacion Espanola de Normalizacion y Certification Sweden Standardiseringskommissionen i Sverige Switzerland Association suisse de normalisation United Kingdom British Standards Institution This British Standard, having been prepared under the direction of the General Mechnical Engineering Standards Policy Committee, was published under the authority of the Standards Board and comes into effect on April 1992 © BSI 12-1998 The following BSI references relate to the work on this standard: Committee reference GME/9 Draft for comment 78/70483 DC ISBN 580 20714 A m e n d m e n t s issued since publication Amd No Date Comments BS EN 20273:1992 Contents Cooperating organizations National foreword Foreword Text of EN 20273 National annex NA (informative) ©BSI 02-1999 Page Inside front cover ii Inside back cover i BS EN 20273:1992 National f o r e w o r d This British Standard has been prepared under the direction of the General Mechanical Engineering Standards Policy Committee and is the English language version of EN 20273:1991, "Fasteners — Clearance holes for bolts and screws" , p u b l i s h e d b y t h e European Committee for Standardization (CEN) It is identical with ISO 273:1979, published by the International Organization for Standardization (ISO) EN 20273:1991 was produced as a result of international discussion in which the UK took an active part BS 4186:1984 was identical to ISO 273:1979 but is now superseded and withdrawn A British Standard does not purport to include all the necessary provisions of a contract Users of British Standards are responsible for their correct application C o m p l i a n c e w i t h a B r i t i s h S t a n d a r d d o e s n o t o f itself c o n f e r i m m u n i t y f r o m legal o b l i g a t i o n s S u m m a r y of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages to 4, an inside back cover 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 ii ©BSI 02-1999 EUROPEAN STANDARD EN 20273 NORME EUROPEENNE EUROPAISCHE NORM October 1991 UDC 621.882.2:621.882.15 Descriptors: Fasteners, bolts, screws, dimensions, hole size, dimensional tolerances English version Fasteners — Clearance holes for bolts and screws (ISO 273:1979) E l e m e n t s de f i x a t i o n — T r o u s de p a s s a g e p o u r boulons e t vis (ISO 273:1979) Mechanische Verbindungselemente — Durchgangslocher fu r Schrauben (ISO 273:1979) This European Standard was approved by CEN on 1991-10-10 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 standards 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 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, Spain, Sweden, Switzerland and United Kingdom CEN European Committee for Standardization Comite Europeen de Normalisation Europaisches Komitee f u r Normung C e n t r a l S e c r e t a r i a t : r u e d e S t a s s a r t 36, B-1050 B r u s s e l s © CEN 1991 Copyright reserved to all CEN members Ref No EN 20273:1991 E EN 20273:1991 Foreword In 1990, ISO 273:1979 was submitted to the CEN P.Q procedure Following the positive result of the P.Q., CEN/BT agreed to submit ISO 273:1979 with the following modifications to Formal Vote In the French version, replace — "boulon" by "vis", — '"boulon, vis" by "vis" In accordance with the Common CEN/CENELEC Rules, 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, Sweden, Swtizerland and United Kingdom Contents Foreword Scope and field of application Dimensions Page 3 © BSI 02-1999 EN 20273:1991 S c o p e a n d field of a p p l i c a t i o n This International Standard specifies clearance hole diameters for general purpose applications These values result from bearing area calculations in connection with ISO bolt and nut product standards NOTE Clearance holes for special applications should be selected on the basis of design requirements Dimensions • / Dimensions in milimetres Clearance hole d h Thread diameter d 1,2 1,4 1,6 1,8 25 3,5 4,5 10 12 14 16 18 20 22 24 27 30 33 36 39 ©BSI 02-1999 Series: fine 1,1 1,3 1,5 1,7 2,2 2,7 3,2 3,7 4,3 4,8 5,3 6,4 7,4 8,4 10,5 13 15 17 19 21 23 25 28 31 34 37 40 medium 12 1,4 1,6 1,8 2,1 2,4 2,9 3,4 3,9 4,5 5,5 6,6 7,6 11 13,5 15,5 17,5 20 22 24 26 30 33 36 39 42 coarse 1,3 1,5 1,8 2,2 2,6 3.1 3,6 4,2 4,8 5,3 5,8 10 12 14,5 16,5 18,5 21 24 26 28 32 35 38 42 45 Clearance h o l e d h Thread diameter d 42 45 48 52 56 60 64 68 72 76 80 85 90 95 100 105 110 115 120 125 130 140 150 Series: fine 43 46 50 54 58 62 66 70 74 78 82 87 93 98 104 109 114 119 124 129 134 144 155 medium 45 48 52 56 62 66 70 74 78 82 86 91 96 101 107 112 117 122 127 132 137 147 158 coarse 48 52 56 62 66 70 74 78 82 86 91 96 101 107 112 117 122 127 132 137 144 155 165 EN 20273:1991 The following tolerance fields are given for information only, for use where it is desirable to specify tolerances: fine series: H12 medium series: H13 coarse series: H14 In cases where it is necessary to avoid interference between the edge of the hole and the underhead fillet of the bolt, a chamfer is recommended © BSI 02-1999 BS EN 20273:1992 National annex NA (informative) Committees responsible The United Kingdom participation in the preparation of this European Standard was entrusted by the General Mechanical Engineering Standards Policy Committee (GME/-) to Technical Committee GME/9, upon which the following bodies were represented: BEAMA Ltd British Constructional Steelwork Association Ltd British Industrial Fasteners Federation British Railways Board British Steel Industry British Steel Industry (Wire Section) Gauge and Tool Makers' Association Ministry of Defence Society of Motor Manufacturers and Traders Ltd Washer Manufacturers' Association of Great Britain The following bodies also participated in the preparation of the standard, through subcommittees and panels: Defence Manufacturers' Association General Municipal Boilermaker and Allied Trades Union Screw Thread Tool Manufacturers' Association Society of British 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