1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ICS 21.040.10 ISBN 0-626-14724-7 SANS 1700-2-2:2003 Edition 1 ISO 261:1998 Edition 2 SOUTH AFRICAN NATIONAL STANDARD Fasteners Part 2: Screw threads Sect
4、ion 2: ISO general purpose metric screw threads General plan This national standard is the identical implementation of ISO 261:1998 and is adopted with the permission of the International Organization for Standardisation. Published by Standards South Africa 1 dr lategan road groenkloof private bag x
5、191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa 2003 SANS 1700-2-2:2003 Edition 1 ISO 261:1998 Edition 2 Table of changes Change No. Date Scope National foreword This South African standard was approved by National Committee ST
6、ANSA TC 5120.01, Screw threads and fasteners, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. AReference numberISO 261:1998(E)INTERNATIONALSTANDARDISO261Second edition1998-12-15ISO general purpose metric screwthreads General planFiletages
7、 mtriques ISO pour usages gnraux Vue densembleISO 261:1998(E) ISO 1998All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronicor mechanical, including photocopying and microfilm, without permission in writing f
8、rom the publisher.International Organization for StandardizationCase postale 56 CH-1211 Genve 20 SwitzerlandInternet isoiso.chPrinted in SwitzerlandiiForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISOmember bodies). The work o
9、f preparing International Standards is normally carried out through ISO technicalcommittees. Each member body interested in a subject for which a technical committee has been established hasthe right to be represented on that committee. International organizations, governmental and non-governmental,
10、 inliaison with ISO, also take part in the work. ISO collaborates closely with the International ElectrotechnicalCommission (IEC) on all matters of electrotechnical standardization.Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.Public
11、ation as an International Standard requires approval by at least 75 % of the member bodies casting a vote.International Standard ISO 261 was prepared by Technical Committee ISO/TC 1, Screw threads, SubcommitteeSC 1, Basic data.This second edition cancels and replaces the first edition (ISO 261:1973)
12、 which has been technically revised.INTERNATIONAL STANDARD ISO ISO 261:1998(E)1ISO general purpose metric screw threads General plan1 ScopeThis International Standard specifies ISO general purpose metric screw threads (M) having basic profile accordingto ISO 68-1. Basic dimensions are given in ISO 7
13、24. For tolerances see ISO 965-1.2 Normative referencesThe following standards contain provisions which, through reference in this text, constitute provisions of thisInternational Standard. At the time of publication, the editions indicated were valid. All standards are subject torevision, and parti
14、es to agreements based on this International Standard are encouraged to investigate thepossibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintainregisters of currently valid International Standards.ISO 68-1:1998, ISO general purpose screw threa
15、ds Basic profile Part 1: Metric screw threads.ISO 262:1998, ISO general purpose metric screw threads Selected sizes for screws, bolts and nuts.ISO 724:1993, ISO general purpose metric screw threads Basic dimensions.ISO 965-1:1998, ISO general purpose metric screw threads Tolerances Part 1: Principle
16、s and basic data.ISO 5408:1983, Cylindrical screw threads Vocabulary.3 DefinitionsFor the purposes of this International Standard, the definitions given in ISO 5408 apply.4 DesignationA screw thread in conformity with this International Standard shall be designated according to ISO 965-1.ISO 261:199
17、8(E)ISO25 Choice of diameter and pitch5.1 Choose, for preference, diameters in column 1 of table 2 and, if necessary, in column 2 and then in column 3.Diameter 35 mm, and pitch 1,25 mm of diameter 14 mm shall be used only for the special cases indicated in thefootnotes.Pitches shown in parentheses a
18、re to be avoided as far as possible.5.2 The words “coarse“ and “fine“ are given in order to conform to usage. No concept of quality shall, however, beassociated with these words.It shall be understood that the “coarse“ pitches are the largest metric pitches used in current practice.5.3 For the diame
19、ter (or the diameter range) selected, choose one of the pitches shown on the corresponding line(or lines).5.4 If screw threads finer than those appearing in table 2 are found necessary, only the following pitches shall beused:3 mm; 2 mm; 1,5 mm; 1 mm; 0,75 mm; 0,5 mm; 0,35 mm; 0,25 mm; 0,2 mmWhen se
20、lecting such pitches, take into account the fact that there is increasing difficulty in complying withtolerances as the diameter is increased for a given pitch. It is suggested, that diameters larger than those shown intable 1 should generally not be used with the pitches indicated.Table 1 Maximum n
21、ominal diameterDimensions in millimetresPitch Maximum nominal diameter0,50,7511,523223380150200300ISOISO 261:1998(E)3Table 2 Nominal diameter/pitchDimensions in millimetresNominal diameter D, d Pitch PCol. 11st choiceCol. 22nd choiceCol. 33rd choicecoarse fine3 2 1,5 1,25 1 0,75 0,5 0,35 0,25 0,21 0
22、,25 0,21,21,11,40,250,250,30,20,20,21,621,80,350,350,4 0,250,20,22,532,2 0,450,450,50,350,350,2543,54,50,60,70,750,50,50,35565,50,81 0,750,50,587911,251,25110,750,750,751012111,51,51,75 1,51,251,251110,750,75161415221,51,51,51,25a1112018172,52,5221,51,51,51112422252,532221,51,51,51112726283221,51,51
23、,5113033323,53,5(3)(3)2221,51,51,51363935b384433221,51,51,51,5(continued)ISO 261:1998(E)ISO4Table 2 (continued)Dimensions in millimetresNominal diameter D, d Pitch PCol. 1 Col. 2 Col. 3 coarse fine1st choice 2nd choice 3rd choice 8 6 4 3 2 1,54245404,54,5443332221,51,51,548525055443332221,51,51,5565
24、5585,54443332221,51,51,56460625,564443332221,51,51,5686570664443332221,51,51,5727675664443332221,51,51,580788264321,590859566644433322210011010566644433322212511512086664443332221401301358866644433322215014515586664443332216017016588666444333180175185866644433320019019588666444333(continued)ISOISO 2
25、61:1998(E)5Table 2 (concluded)Dimensions in millimetresNominal diameter D, d Pitch PCol. 1 Col. 2 Col. 3 coarse fine1st choice 2nd choice 3rd choice 8 6 4 3 2 1,5210205215866644433322022523088666444333240235245866644433325026025588666444326527027586664442802852908866644430029586644aOnly for spark plugs for engines.bOnly for locking nuts for bearings.
