1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 5459:2011Geometrical productspecifications (GPS) Geometrical tolerancing Datums and datum systems(ISO 5459:2011)BS EN ISO 5459:2011 BRITISH STANDARDNational forewordThi
2、s British Standard is the UK implementation of EN ISO 5459:2011.It supersedes BS ISO 5459:1981 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee TDW/4, Technical Product Realization.A list of organizations represented on this committee can beobtained on r
3、equest to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 53481 2ICS 01.100.20; 17.040.10Compliance with a British Standard cannot confer immunity fromlegal obligations.This
4、 British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 August 2011.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 5459 August 2011 ICS 01.100.20; 17.040.10 English Version Geometrical prod
5、uct specifications (GPS) - Geometrical tolerancing - Datums and datum systems (ISO 5459:2011) Spcification gomtrique des produits (GPS) - Tolrancement gomtrique - Rfrences spcifies et systmes de rfrences spcifies (ISO 5459:2011) Geometrische Produktspezifikation (GPS) - Geometrische Tolerierung - Be
6、zge und Bezugssysteme (ISO 5459:2011)This European Standard was approved by CEN on 18 May 2011. 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-d
7、ate lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translatio
8、n under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Fr
9、ance, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE
10、FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 5459:2011: EBS EN ISO 5459:2011EN ISO 5459:2011 (E) 3 Foreword This document (EN ISO 5459:2011) has been prepa
11、red by Technical Committee ISO/TC 213 “Dimensional and geometrical product specifications and verification“ in collaboration with Technical Committee CEN/TC 290 “Dimensional and geometrical product specification and verification” the secretariat of which is held by AFNOR. This European Standard shal
12、l be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2012, and conflicting national standards shall be withdrawn at the latest by February 2012. Attention is drawn to the possibility that some of the elements of this do
13、cument may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard
14、: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kin
15、gdom. Endorsement notice The text of ISO 5459:2011 has been approved by CEN as a EN ISO 5459:2011 without any modification. BS EN ISO 5459:2011ISO 5459:2011(E) ISO 2011 All rights reserved iiiContents Page Foreword iv Introduction.v 1 Scope1 2 Normative references1 3 Terms and definitions .2 4 Symbo
16、ls6 5 Role of datums.7 6 General concepts 9 6.1 General .9 6.2 Intrinsic characteristics of surfaces associated with datum features.10 6.2.1 General .10 6.2.2 A single datum established from a single feature .10 6.2.3 Common datum established from two or more single features simultaneously10 6.2.4 D
17、atum systems established in a defined sequence from two or more single features.12 6.3 Single datums, common datums and datum systems 12 6.3.1 General .12 6.3.2 Single datums 12 6.3.3 Common datums .14 6.3.4 Datum systems 14 7 Graphical language .17 7.1 General .17 7.2 Indication of datum features 1
18、7 7.2.1 Datum feature indicator 17 7.2.2 Datum feature identifier 18 7.2.3 Datum targets 18 7.3 Specification of datums and datum systems .21 7.4 Indication and meaning of rules 21 7.4.1 General .21 7.4.2 Rules.22 Annex A (normative) Association for datums37 Annex B (informative) Invariance classes
19、47 Annex C (informative) Examples .49 Annex D (informative) Former practices.71 Annex E (informative) Examples of a datum system or a common datum established with contacting features .73 Annex F (normative) Relations and dimensions of graphical symbols 79 Annex G (informative) Relationship to the G
20、PS matrix model .80 Bibliography81 BS EN ISO 5459:2011ISO 5459:2011(E) iv ISO 2011 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normall
21、y carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the
22、work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare In
23、ternational Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of
24、 the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 5459 was prepared by Technical Committee ISO/TC 213, Dimensional and geometrical product specification and verification. This second edition cancel
25、s and replaces the first edition (ISO 5459:1981), which has been technically revised. BS EN ISO 5459:2011ISO 5459:2011(E) ISO 2011 All rights reserved vIntroduction ISO 5459 is a geometrical product specification (GPS) standard and is to be regarded as a general GPS standard (see ISO/TR 14638). It i
26、nfluences the chain links 1 to 3 of the chain of standards on datums. The ISO/GPS Masterplan given in ISO/TR 14638 gives an overview of the ISO/GPS system of which this standard is a part. The fundamental rules of ISO/GPS given in ISO 8015 apply to this standard and the default decision rules given
27、in ISO 14253-1 apply to specifications made in accordance with this standard unless otherwise indicated. For more detailed information of the relation of this International Standard to the GPS matrix model, see Annex G. For the definitive presentation (proportions and dimensions) of symbols for geom
28、etrical tolerancing, see ISO 7083. The previous version of ISO 5459 dealt only with planes, cylinders and spheres being used as datums. There is a need to consider all types of surfaces, which are increasingly used in industry. The definitions of classes of surfaces as given in Annex B are exhaustiv
29、e and unambiguous. This edition of ISO 5459 applies new concepts and terms that have not been used in previous ISO GPS standards. These concepts are described in detail in ISO/TR 14638, ISO 17450-1 and ISO 17450-2; therefore, it is recommended to refer to these standards when using ISO 5459. This In
30、ternational Standard provides tools to express location or orientation constraints, or both, for a tolerance zone. It does not provide information about the relationship between datums or datum systems and functional requirements or applications. BS EN ISO 5459:2011BS EN ISO 5459:2011INTERNATIONAL S
31、TANDARD ISO 5459:2011(E) ISO 2011 All rights reserved 1Geometrical product specifications (GPS) Geometrical tolerancing Datums and datum systems 1 Scope This International Standard specifies terminology, rules and methodology for the indication and understanding of datums and datum systems in techni
32、cal product documentation. This International Standard also provides explanations to assist the user in understanding the concepts involved. This International Standard defines the specification operator (see ISO 17450-2) used to establish a datum or datum system. The verification operator (see ISO
33、17450-2) can take different forms (physically or mathematically) and is not the subject of this International Standard. NOTE The detailed rules for maximum and least material requirements for datums are given in ISO 2692. 2 Normative references The following referenced documents are indispensable fo
34、r the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 128-24:1999, Technical drawings General principles of presentation Part 24: Lines on mechanical engi
35、neering drawings ISO 1101:2004, Geometrical Product Specifications (GPS) Geometrical tolerancing Tolerances of form, orientation, location and run-out ISO 1101:2004/Amd 1:1), Geometrical Product Specifications (GPS) Geometrical tolerancing Tolerances of form, orientation, location and run-out Amendm
36、ent 1: Representation of specifications in the form of a 3D model ISO 2692:2006, Geometrical product specifications (GPS) Geometrical tolerancing Maximum material requirement (MMR), least material requirement (LMR) and reciprocity requirement (RPR) ISO 3098-0, Technical product documentation Letteri
37、ng Part 0: General requirements ISO 3098-5, Technical product documentation Lettering Part 5: CAD lettering of the Latin alphabet, numerals and marks ISO 14660-1:1999, Geometrical Product Specifications (GPS) Geometrical features Part 1: General terms and definitions ISO 17450-1, Geometrical product
38、 specifications (GPS) General concepts Part 1: Model for geometrical specification and verification ISO 17450-2, Geometrical product specifications (GPS) General concepts Part 2: Basic tenets, specifications, operators and uncertainties ISO 81714-1, Design of graphical symbols for use in the technic
39、al documentation of products Part 1: Basic rules 1) To be published. BS EN ISO 5459:2011ISO 5459:2011(E) 2 ISO 2011 All rights reserved3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 1101, ISO 2692, ISO 14660-1, ISO 17450-1, ISO 17450-2 and the follo
40、wing apply. 3.1 situation feature point, straight line, plane or helix from which the location and orientation of features, or both, can be defined 3.2 datum feature real (non-ideal) integral feature used for establishing a datum NOTE 1 A datum feature can be a complete surface, a portion of a compl
41、ete surface, or a feature of size. NOTE 2 An illustration showing the relations between datum feature, associated feature and datum is given in Figure 4. 3.3 associated feature associated feature for establishing a datum ideal feature which is fitted to the datum feature with a specific association
42、criterion NOTE 1 The type of the associated feature is by default the same as the type of the nominal integral feature used to establish the datum (for an exception see 7.4.2.5). NOTE 2 The associated feature for establishing a datum simulates the contact between the real surface of the workpiece an
43、d other components. NOTE 3 An illustration showing the relations between datum feature, associated feature and datum is given in Figure 4. 3.4 datum one or more situation features of one or more features associated with one or more real integral features selected to define the location or orientatio
44、n, or both, of a tolerance zone or an ideal feature representing for instance a virtual condition NOTE 1 A datum is a theoretically exact reference; it is defined by a plane, a straight line or a point, or a combination thereof. NOTE 2 The concept of datums is inherently reliant upon the invariance
45、class concept (see Annex A and Annex B). NOTE 3 Datums with maximum material condition (MMC) or least material condition (LMC) are not covered in this International Standard (see ISO 2692). NOTE 4 When a datum is established, for example, on a complex surface, the datum consists of a plane, a straig
46、ht line or a point, or a combination thereof. The modifier SL, PL or PT, or a combination thereof, can be attached to the datum letter to limit the situation feature(s) taken into account relative to the surface. NOTE 5 An illustration showing the relation between datum feature, associated feature a
47、nd datum is given in Figure 4. 3.5 primary datum datum that is not influenced by constraints from other datums 3.6 secondary datum datum, in a datum system, that is influenced by an orientation constraint from the primary datum in the datum system BS EN ISO 5459:2011ISO 5459:2011(E) ISO 2011 All rig
48、hts reserved 33.7 tertiary datum datum, in a datum system, that is influenced by constraints from the primary datum and the secondary datum in the datum system 3.8 single datum datum established from one datum feature taken from a single surface or from one feature of size NOTE The invariance class
49、of a single surface can be complex, prismatic, helical, cylindrical, revolute, planar or spherical. A set of situation features defining the datum (see Table B.1) corresponds to each type of single surface. 3.9 common datum datum established from two or more datum features considered simultaneously NOTE To define a common datum, it is necessary to consider the collection surface created by the considered datum features. The invariance class of a collection surface can be complex, prismatic,