1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 25378:2011Geometrical productspecifications (GPS) Characteristics and conditions DefinitionsBS EN ISO 25378:2011 BRITISH STANDARDNational forewordThis British Standard
2、is the UK implementation of EN ISO25378:2011.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 request to its secretary.This publication does not purport to include
3、all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 57494 8ICS 17.040.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and S
4、trategy Committee on 31 May 2011.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 25378 April 2011 ICS 17.040.01 English Version Geometrical product specifications (GPS) - Characteristics and conditions - Definitions (ISO 25378:2011) Spcif
5、ication gomtrique des produits - Caractristiques et conditions - Dfinitions (ISO 25378:2011) Geometrische Produktspezifikation (GPS) - Merkmale und Bedingungen - Begriffe (ISO 25378:2011) This European Standard was approved by CEN on 7 August 2010. CEN members are bound to comply with the CEN/CENELE
6、C 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 CEN-CENELEC Management Centre or
7、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 CEN-CENELEC Management Centre has the same status as the offic
8、ial versions. CEN members are the national standards bodies of 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, Slov
9、akia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE 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
10、 for CEN national Members. Ref. No. EN ISO 25378:2011: EBS EN ISO 25378:2011EN ISO 25378:2011 (E) 3 Foreword This document (EN ISO 25378:2011) has been prepared by Technical Committee ISO/TC 213 “Dimensional and geometrical product specifications and verification“ in collaboration with Technical Com
11、mittee CEN/TC 290 “Dimensional and geometrical product specification and verification” the secretariat of which is held by AFNOR. 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 October 2011, and
12、conflicting national standards shall be withdrawn at the latest by October 2011. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. Accor
13、ding to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Ita
14、ly, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 25378:2011 has been approved by CEN as a EN ISO 25378:2011 without any modification. BS EN ISO 25378:201
15、1ISO 25378:2011(E) ISO 2011 All rights reserved vIntroduction This International Standard is a Geometrical product specifications (GPS) standard and is to be regarded as a global GPS standard (see ISO/TR 14638). It influences all chain links of all chains of standards in the general GPS matrix. To f
16、acilitate the reading and the understanding of this International Standard, it is essential to refer to ISO 17450-1 and ISO/TS 17450-2. Geometrical characteristics exist in three “worlds”: the world of nominal geometrical definition, where an ideal representation of the future workpiece is defined b
17、y the designer; the world of specification, where several representations of the future workpiece are imagined by the designer; the world of verification, where one or several representations of a given workpiece are identified in the application of measuring procedure(s). A GPS specification define
18、s requirements through a geometrical characteristic and condition. In the world of verification, mathematical operations can be distinguished from physical operations. The physical operations are the operations based on physical procedures; they are generally mechanical, optical or electromagnetic.
19、The mathematical operations are mathematical treatments of the sampling of the workpiece. This treatment is generally achieved by computing or electronic treatment. It is important to understand the relationship between these three worlds. These specifications, characteristics and conditions, generi
20、cally defined in this International Standard, are well suited to define requirements of rigid parts and assemblies and can also be applied to non-rigid parts and assemblies. BS EN ISO 25378:2011BS EN ISO 25378:2011INTERNATIONAL STANDARD ISO 25378:2011(E) ISO 2011 All rights reserved 1Geometrical pro
21、duct specifications (GPS) Characteristics and conditions Definitions 1 Scope This International Standard defines general terms for geometrical specifications, characteristics and conditions. These definitions are based on concepts developed in ISO 17450-1 and ISO 22432 and they are given by using a
22、mathematical description based on Annex B of ISO 17450-1:2011. This International Standard is not intended for industrial use as such among designers, but is aimed to serve as the “road map” mapping out the requirements based on geometrical features, thus enabling future standardization for industry
23、 and software makers in a consistent manner. This International Standard defines general types of geometrical characteristics and conditions which can be used in GPS. These descriptions are applicable to a workpiece, an assembly, a population of workpieces, and a population of assemblies. These defi
24、nitions are based on concepts of operators and the duality principle contained in ISO 17450-1 and ISO/TS 17450-2 and on the description of types of geometrical features defined in ISO 22432. Conceptually, these specification operators can be used as specification operators or as verification operato
25、rs (duality principle). This International Standard is not intended to define GPS specifications, symbology or other types of expression. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited app
26、lies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3534-1:2006, Statistics Vocabulary and symbols Part 1: General statistical terms and terms used in probability ISO 3534-2, Statistics Vocabulary and symbols Part 2: Applied statistics
27、ISO 17450-1:2011, Geometrical product specifications (GPS) General concepts Part 1: Model for geometrical specification and verification ISO/TS 17450-2, Geometrical product specifications (GPS) General concepts Part 2: Basic tenets, specifications, operators and uncertainties BS EN ISO 25378:2011ISO
28、 25378:2011(E) 2 ISO 2011 All rights reservedISO 224321), Geometrical product specifications (GPS) Features utilized in specification and verification 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 3534-1, ISO 3534-2 and ISO 17450-1 and the followin
29、g apply. 3.1 geometrical specification expression of a set of one or more conditions on one or more geometrical characteristics NOTE 1 A specification can express a combination of individual conditions on an individual characteristic or a population condition on a population characteristic. NOTE 2 A
30、 specification consists of one or more single specifications. These single specifications can be individual specifications, population specifications or any combination. 3.2 condition combination of a limit value and a binary relational mathematical operator EXAMPLE 1 “be less than or equal to 6,3”,
31、 the expression of this condition can be, for instance: 6,3 max or U 6,3. Mathematically: let X be the considered value of the characteristic, the condition is X u 6,3. EXAMPLE 2 “be greater than or equal to 0,8”, the expression of this condition can be, for instance: 0,8 min or L 0,8. Mathematicall
32、y: let X be the considered value of the characteristic, the condition is 0,8 u X. EXAMPLE 3 a set of two complementary conditions (lower and upper limits) can be expressed through, for instance: 10,2 9,8, 9,80,40+, 10 0,2, or 9,90,30,1+. Mathematically: let X be the considered value of the character
33、istic, the condition is 9,8 u X u 10,2. EXAMPLE 4 “be less than or equal to R, R being given by a function, R = (X 2+ Y 2) 0,85, X and Y being the ordinates of the coordinate system. NOTE 1 A binary relational mathematical operator is a mathematical concept which generalizes the notion as “greater t
34、han or equal to” in arithmetic, or “is item of the set” in set theory. NOTE 2 The limit value can be defined for any individual workpiece or for populations of workpieces. NOTE 3 The limit value can be independent of a coordinate system or dependent upon it. In the latter case, the limit value depen
35、ds on the function of the ordinates of the coordinate system or graphical ordinate system. NOTE 4 The limit value can be determined by a statistical tolerancing approach, by an arithmetical tolerancing (worst case) approach or by other means. The manner of determining the limit value and the choice
36、of condition is not the subject of this International Standard. NOTE 5 Two possible inequality relations exist: the characteristic value can be less than or equal to the limit value (upper limit); the characteristic value can be greater than or equal to the limit value (lower limit). 1) In preparati
37、on. BS EN ISO 25378:2011ISO 25378:2011(E) ISO 2011 All rights reserved 33.2.1 individual condition condition where the limit value applies to any value of an individual characteristic coming from any workpiece EXAMPLE An individual condition used in an individual specification: the individual charac
38、teristic value shall be less than or equal to 10,2. Mathematically: let X be the considered value of the individual characteristic, the condition is X u 10,2. NOTE An individual condition can be used alone or in combination with a population condition on the corresponding population characteristic.
39、3.2.2 population condition condition where the limits apply to the value of the population characteristic EXAMPLE A population condition used in a population specification: the value of a population characteristic shall be less than or equal to 10,1. Mathematically: let X be the considered value of
40、the population characteristic (mean value of the population of global individual characteristic values), the condition is 10,1X u . NOTE The population condition can be used for statistical process control (SPC). 3.3 geometrical characteristic individual characteristic or population characteristic r
41、elated to the geometry NOTE 1 This International Standard applies to the field of geometry and therefore, throughout this standard, only “geometrical characteristics” are used. The term “characteristic” is defined in ISO 9000:2005, 3.5.1. NOTE 2 The geometrical characteristic permits the evaluation
42、of a quantity which could be associated to, for instance, an angular dimension, a linear dimension, an area, a volume, etc. 3.3.1 individual characteristic individual geometrical characteristic single geometrical property of one or more geometrical features belonging to a workpiece EXAMPLE The two-p
43、oint diameter is an individual characteristic and the result is mathematically varying along the cylindrical feature: it is a local individual characteristic. The minimum circumscribed cylinder diameter is an individual characteristic and the result is mathematically unique: it is a global individua
44、l characteristic. NOTE 1 A local characteristic can be single or calculated. NOTE 2 The evaluation of an individual characteristic does not necessarily give a unique result (it can be characterized as a local individual characteristic or a global individual characteristic). 3.3.1.1 local individual
45、characteristic individual characteristic of which the result of evaluation is not unique EXAMPLE 1 The two-point diameter is an individual characteristic and the result varies mathematically along the cylindrical feature: it is a local individual characteristic. EXAMPLE 2 See 5.3. NOTE 1 A local ind
46、ividual characteristic is evaluated on portion feature(s) and can be a direct characteristic or a calculated characteristic. The local diameter measured between two points is a direct local characteristic. The mean of local diameters measured between two points for a given section is a calculated lo
47、cal characteristic. NOTE 2 The result of an evaluation is related to an entire feature; a single two-point diameter is in itself unique. BS EN ISO 25378:2011ISO 25378:2011(E) 4 ISO 2011 All rights reserved3.3.1.2 global individual characteristic individual characteristic of which the result of evalu
48、ation is unique EXAMPLE 1 The minimum circumscribed cylinder diameter is a direct global individual characteristic (the result is mathematically unique). EXAMPLE 2 The maximum of two-point diameters along a given cylinder is a calculated global individual characteristic (the result comes from a stat
49、istic and is mathematically unique). NOTE The result of evaluation of a global individual characteristic can come from a unique evaluation or a statistic of a set of results of evaluation of a local individual characteristic, characterized as direct and calculated, respectively. 3.3.2 population characteristic statistic defined from the characteristic values, obtained on the population of workpieces or the population of assemblies NOTE 1 Population characteristics are used to consider a total population of wor
