SIST EN ISO 25378:2011
(Main)Geometrical product specifications (GPS) - Characteristics and conditions - Definitions (ISO 25378:2011)
Geometrical product specifications (GPS) - Characteristics and conditions - Definitions (ISO 25378:2011)
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 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 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 definitions 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 operators
(duality principle).
This International Standard is not intended to define GPS specifications, symbology or other types of
expression.
Geometrische Produktspezifikation (GPS) - Merkmale und Bedingungen - Begriffe (ISO 25378:2011)
Dieses Dokument legt die allgemeinen Begriffe für die geometrische Spezifikation, die Merkmale und die Bedingungen fest. Diese Festlegungen beruhen auf den in den Dokumenten ISO/TS 17450 1 und ISO 22432 entwickelten Vorstellungen und sie sind unter Verwendung einer mathematischen Beschreibung angegeben, welche auf dem Anhang B des Dokuments ISO/TS 17450 1 beruht.
Es war nicht die Absicht, dass diese internationale Norm als solche für die industrielle Anwendung unter Konstrukteuren verwendet wird, sondern sie zielt vielmehr darauf ab, als ein Leitfaden zu dienen, der die gegenseitige Beziehung zwischen Geometrieelementen abbildet, um damit eine zukünftige Standardisierung für die Industrie und für Programmierer in einer folgerichtigen Art und Weise zu ermöglichen.
Spécification géométrique des produits - Caractéristiques et conditions - Définitions (ISO 25378:2011)
L'ISO 25378:2011 définit les termes généraux relatifs aux spécifications, caractéristiques et conditions géométriques. Ces définitions reposent sur des concepts développés dans l'ISO 17450‑1 et l'ISO 22432. Elles sont accompagnées d'une description mathématique basée sur l'Annexe B de l'ISO 17450‑1:2011.
L'ISO 25378:2011 n'est pas destinée à un usage industriel en l'état par les concepteurs. Elle fait office de «carte routière» mettant en évidence les exigences reposant sur les fonctions géométriques, permettant ainsi de concevoir de manière cohérente une future normalisation destinée aux industriels et aux fabricants de logiciels.
L'ISO 25378:2011 définit les types généraux de caractéristiques et conditions qui peuvent être utilisés en GPS. Ces descriptions sont applicables
à la pièce,
à un assemblage,
à une population de pièces, et
à une population d'assemblages.
Ces définitions s'appuient sur les concepts des opérateurs et du principe de dualité définis dans l'ISO 17450‑1 et l'ISO/TS 17450‑2 et sur les descriptions des éléments géométriques données dans l'ISO 22432.
De manière conceptuelle, ces opérateurs de spécification peuvent être utilisés comme des opérateurs de spécification ou des opérateurs de vérification (principe de dualité).
L'ISO 25378:2011 n'a pas pour but de définir les spécifications GPS, leurs symboles ou d'autres types d'expressions.
Specifikacija geometrijskih veličin izdelka - Značilnosti in razmere - Definicije (ISO 25378:2011)
Ta mednarodni standard opredeljuje splošno terminologijo za geometrijske specifikacije, značilnosti in razmere.
Definicije so zasnovane na konceptih, razvitih v ISO 17450-1 in ISO 22432, in so podane z uporabo matematičnega opisa na osnovi dodatka B ISO 17450-1:2011.
Ta mednarodni standard kot tak ni namenjen industrijski uporabi pri načrtovalcih, pač pa naj se uporablja kot »zemljevid«, ki orisuje zahteve na osnovi geometrijskih lastnosti, in s tem dosledno omogoča prihodnjo standardizacijo za industrijo in izdelovalce programske opreme.
Ta mednarodni standard opredeljuje splošne tipe geometrijskih značilnosti in razmer, ki se lahko uporabljajo pri GPS. Ti opisi veljajo za
⎯ izdelek,
⎯ sestav,
⎯ množico izdelkov in
⎯ množico sestavov.
Te definicije temeljijo na konceptih operatorjev in načelu dvojnosti iz ISO 17450-1 in ISO/TS 17450-2 ter na opisu tipov geometrijskih značilnosti, opredeljenih v ISO 22432.
Konceptualno se specifikacijski operatorji lahko uporabljajo kot specifikacijski operatorji ali kot overitveni operatorji (načelo dvojnosti).
Ta mednarodni standard ni namenjen opredelitvi specifikacij GPS, simbologije ali drugih vrst izražanja.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 25378:2011
01-december-2011
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND=QDþLOQRVWLLQUD]PHUH'HILQLFLMH ,62
Geometrical product specifications (GPS) - Characteristics and conditions - Definitions
(ISO 25378:2011)
Geometrische Produktspezifikation (GPS) - Merkmale und Bedingungen - Begriffe (ISO
25378:2011)
Spécification géométrique des produits - Caractéristiques et conditions - Définitions (ISO
25378:2011)
Ta slovenski standard je istoveten z: EN ISO 25378:2011
ICS:
17.040.40 6SHFLILNDFLMDJHRPHWULMVNLK Geometrical Product
YHOLþLQL]GHOND *36 Specification (GPS)
SIST EN ISO 25378:2011 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 25378:2011
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SIST EN ISO 25378:2011
EUROPEAN STANDARD
EN ISO 25378
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2011
ICS 17.040.01
English Version
Geometrical product specifications (GPS) - Characteristics and
conditions - Definitions (ISO 25378:2011)
Spécification géométrique des produits - Caractéristiques Geometrische Produktspezifikation (GPS) - Merkmale und
et conditions - Définitions (ISO 25378:2011) 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/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 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 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 official 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, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 25378:2011: E
worldwide for CEN national Members.
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SIST EN ISO 25378:2011
EN ISO 25378:2011 (E)
Contents Page
Foreword .3
2
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SIST EN ISO 25378:2011
EN ISO 25378:2011 (E)
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 Committee
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 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.
According 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, Italy, 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.
3
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SIST EN ISO 25378:2011
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SIST EN ISO 25378:2011
INTERNATIONAL ISO
STANDARD 25378
First edition
2011-04-01
Geometrical product specifications
(GPS) — Characteristics and
conditions — Definitions
Spécification géométrique des produits — Caractéristiques et
conditions — Définitions
Reference number
ISO 25378:2011(E)
©
ISO 2011
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
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All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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Published in Switzerland
ii © ISO 2011 – All rights reserved
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
4 General presentation.15
4.1 General principles of the specifications .15
4.2 General principle of the characteristics.15
5 Illustration of GPS characteristics.16
5.1 General .16
5.2 Single and relationship characteristics .17
5.3 Local and global characteristics.20
5.4 Deviated and reference feature.20
5.5 Independent characteristics.21
5.6 Zone characteristic.30
5.7 Gauge characteristic.34
5.8 Assembly or sub-assembly characteristic .39
6 Relations between terms related to characteristic .44
Annex A (informative) Overview diagrams.46
Annex B (normative) Basic (geometrical) characteristic.49
Annex C (informative) Relation to the GPS matrix model.57
Bibliography.58
© ISO 2011 – All rights reserved iii
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally 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 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 International 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 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 25378 was prepared by Technical Committee ISO/TC 213, Dimensional and geometrical product
specifications and verification.
iv © ISO 2011 – All rights reserved
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
Introduction
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 facilitate 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 by 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 defines 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. 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, generically 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.
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SIST EN ISO 25378:2011
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SIST EN ISO 25378:2011
INTERNATIONAL STANDARD ISO 25378:2011(E)
Geometrical product 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 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 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 definitions 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 operators
(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 applies. 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
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
© ISO 2011 – All rights reserved 1
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
1)
ISO 22432 , 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 following 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 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”, 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.
Mathematically: 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:
+0,4 +0,3
10,2 − 9,8, 9,8 , 10 ± 0,2, or 9,9 . Mathematically: let X be the considered value of the characteristic, the condition
0 −0,1
is 9,8 u X u 10,2.
2 2
EXAMPLE 4 “be less than or equal to R, R being given by a function, R = (X + Y ) × 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
than 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 depends 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 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 preparation.
2 © ISO 2011 – All rights reserved
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
3.2.1
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 characteristic 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.
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 the population characteristic (mean value of
the population of global individual characteristic values), the condition is Xu10,1.
NOTE The population condition can be used for statistical process control (SPC).
3.3
geometrical characteristic
individual characteristic or population characteristic related 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 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-point 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 individual 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 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 individual 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 local characteristic.
NOTE 2 The result of an evaluation is related to an entire feature; a single two-point diameter is in itself unique.
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
3.3.1.2
global individual characteristic
individual characteristic of which the result of evaluation 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 statistic 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 workpieces.
EXAMPLE 1 The arithmetic mean or the standard deviation on the population of workpieces of a global individual
characteristic are population characteristics.
NOTE 2 Population characteristics are only statistically meaningful for GPS characteristics when the value is the result
of global individual characteristics.
EXAMPLE 2 The minimum circumscribed cylinder diameter has one unique value for a given cylindrical feature.
Therefore, a population characteristic based on this individual characteristic value will be statistically meaningful. The two-
point diameter for a given cylindrical feature will vary within a range, dependent upon the form deviations of the feature. In
this case, a population characteristic cannot be defined from the population of values. It could be possible, in this case, to
establish a population characteristic from the maximum value of the two-point diameter along the feature. In this case, the
individual characteristic is a global individual characteristic which is the maximum two-point diameter on a given workpiece.
NOTE 3 The population characteristic can be used, for example, for statistical process control (SPC).
3.4
statistic
completely specified function of random variables
EXAMPLE See Table 1. More information can be found in the ISO 3534 series.
NOTE 1 This definition, taken from ISO 3534-1:2006, 1.8, is associated to notes which are not reproduced in this
International Standard.
NOTE 2 In GPS, the random variables which are used are, in most cases, one-dimensional (scalar). Multidimensional
(vector) variables also exist.
NOTE 3 For a population or a sample of individual characteristic values, at least one statistic can be applied. In GPS, a
statistic can be used on a population of local individual characteristic values taken on one workpiece, or on a population of
global individual characteristic values taken on a population of workpieces.
4 © ISO 2011 – All rights reserved
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
Table 1 — Non-exhaustive list of statistics
a
Description of the statistic
Mathematical description according to ISO 3534-1
the minimum minimum (X)
the maximum maximum (X)
n
the expected value (mean)
1
kk
μ==EX() X , or
∑ i
n
i=1
μ==Eg()X g()Xdp= g(x)dF(x)
⎡⎤
⎣⎦
∫∫
µ− TV
the difference between the average and the target value (TV)
the standard deviation σ= VX()
2
the variance
VX()=−E⎡X E()X ⎤
⎣ ⎦
a
Where X is the characteristic value.
NOTE 4 For some statistical applications (like SPC), it can be necessary to define a “Target Value” (see ISO 7966 and
ISO 3534-2).
3.5
calculated characteristic
local or global individual characteristic obtained from a collection of a set of values of one local individual
characteristic by using a function and not changing the nature of the initial characteristic
EXAMPLE 1 The normal vector obtained from three local individual characteristic vector values is a calculated
characteristic, which is a local individual characteristic (see Figure 1).
EXAMPLE 2 The expected value (mean value) obtained from the population of values of local diameter of the cylinder
in a specific section is a local individual characteristic.
EXAMPLE 3 The expected value (mean value) obtained from the population of values of local diameter of the cylinder
(taking into account the entire cylinder) is a global individual characteristic.
Key
R , R , R local individual characteristic vector values in a coordinate system
1 2 3
C coordinates assigned to the normal vector of the surface
i
JJG
V normal vector of the surface
i
Figure 1 — Calculated characteristic consisting of the angles of a normal vector of a surface
coming from three values of a local individual characteristic
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SIST EN ISO 25378:2011
ISO 25378:2011(E)
3.5.1
direct characteristic
local or global characteristic derived from a single evaluation
3.5.2
transformed characteristic
local or global characteristic which changes the initial characteristic
3.6
combination characteristic
geometrical characteristic obtained from a collection of values related to a set of geometrical characteristics by
using a function
EXAMPLE The volume of a cylinder can be seen as a combination characteristic which is a function of two
geometrical characteristic values: the length and the diameter of the cylinder.
3.7
value of a geometrical characteristic
geometrical characteristic value
signed value with or without a unit resulting from an evaluation of a geometrical characteristic, quantified on a
workpiece or the population of workpieces
NOTE The characteristic value is, in most cases, a uni-dimensional value but can be multidimensional (vector value).
EXAMPLE Local two-point diameter, global minimum circumscribed diameter, vector describing the location and
orientation of a hole axis.
3.7.1
value of an individual characteristic
signed value with or without a unit resulting from an evaluation of an individual characteristic, quantified on
one workpiece
3.7.2
value of a population characteristic
signed value with or without a unit resulting from an evaluation of a population characteristic, quantified on the
population of workpieces
NOTE 1 By using sampling (instead of the whole population), a sampling uncertainty is introduced (see E.4 of
ISO/IEC Guide 98-3:2008).
NOTE 2 The evaluation of a population characteristic is a two-step process:
⎯ evaluation of a set of results of an individual characteristic;
⎯ statistical evaluation of the results of step 1.
NOTE 3 For any individual characteristic value, the value obtained from a simplified verification operator will, in general,
differ from the value obtained from a perfect verification operator. In general, there is no simple way to estimate the
variation of this difference and, in most practical cases, it is simply impossible. It is not unusual for this difference to be of
the same magnitude as the population variation. The variation in the difference may increase or decrease the evaluated
population variation. Because this difference enters into the statistical calculation and affects it in such a significant and
unpredictable way, a meaningful estimation of the uncertainty of the evaluation of the variation of a characteristic in a
population by a simplified verification operator is, in general, very difficult and in most cases impossible. Therefore, it is
only meaningful to use population characteristics in specifications that will be evaluated by verification operators without
method uncertainty.
EXAMPLE 1 It is impossible to define the relationship between the standard deviation of two-point diameters on a
population of workpieces and the standard deviation of the minimum circumscribed cylinder diameter of the same
population of workpieces without complete knowledge of the form deviations of the workpieces and the
...
SLOVENSKI STANDARD
oSIST prEN ISO 25378:2007
01-oktober-2007
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND6SHFLILNDFLMH=QDþLOQRVWLLQUD]PHUH
,62',6
Geometrical product specifications (GPS) - Specification - Characteristics and conditions
(ISO/DIS 25378:2007)
Geometrische Produktspezifikation (GPS) - Technische Beschreibung (Spezifikation) -
Merkmale und Bedingungen (ISO/DIS 25378:2007)
Spécification géométrique des produits - Spécifications - Caractéristiques et conditions
(ISO/DIS 25378:2007)
Ta slovenski standard je istoveten z: prEN ISO 25378
ICS:
17.040.30 Merila Measuring instruments
oSIST prEN ISO 25378:2007 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
DRAFT
prEN ISO 25378
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2007
ICS 17.040.30
English Version
Geometrical product specifications (GPS) - Specification -
Characteristics and conditions (ISO/DIS 25378:2007)
Spécification géométrique des produits - Spécifications -
Caractéristiques et conditions (ISO/DIS 25378:2007)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
CEN/TC 290.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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 Management Centre has the
same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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 United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 25378:2007: E
worldwide for CEN national Members.
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prEN ISO 25378:2007 (E)
Foreword
This document (prEN ISO 25378:2007) has been prepared 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 document is currently submitted to the CEN Enquiry.
Endorsement notice
The text of ISO/DIS 25378:2007 has been approved by CEN as a prEN ISO 25378:2007 without any
modification.
2
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DRAFT INTERNATIONAL STANDARD ISO/DIS 25378
ISO/TC 213 Secretariat: DS
Voting begins on: Voting terminates on:
2007-05-31 2007-10-31
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
Geometrical product specifications (GPS) — Specification —
Characteristics and conditions
Spécification géométrique des produits — Spécifications — Caractéristiques et conditions
ICS 17.040.01
ISO/CEN PARALLEL ENQUIRY
The CEN Secretary-General has advised the ISO Secretary-General that this ISO/DIS covers a subject
of interest to European standardization. In accordance with the ISO-lead mode of collaboration as
defined in the Vienna Agreement, consultation on this ISO/DIS has the same effect for CEN
members as would a CEN enquiry on a draft European Standard. Should this draft be accepted, a
final draft, established on the basis of comments received, will be submitted to a parallel two-month FDIS
vote in ISO and formal vote in CEN.
To expedite distribution, this document is circulated as received from the committee secretariat.
ISO Central Secretariat work of editing and text composition will be undertaken at publication
stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.
THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT, WITH THEIR COMMENTS, NOTIFICATION OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPORTING DOCUMENTATION.
©
International Organization for Standardization, 2007
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ISO/DIS 25378
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©
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ISO/DIS 25378
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 General presentation.15
4.1 General principles of the specifications .15
4.2 General principle of the characteristics.15
5 GPS characteristic.16
5.1 General .16
5.2 Independent characteristics.22
5.3 Zone characteristic.33
5.4 Gauge characteristic.38
5.5 Assembly or sub assembly characteristic.44
Annex A (informative) Overview diagrams.50
Annex B (normative) Basic (geometrical) characteristic.53
B.1 General .53
B.2 Intrinsic characteristic .53
B.3 Situation characteristic.54
Annex C (informative) Relation to the GPS matrix model.62
C.1 Information about this International Standard and its use .62
C.2 Position in the GPS matrix model.62
C.3 Related International Standards .62
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ISO/DIS 25378
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally 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 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 International 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 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 25378 was prepared by Technical Committee ISO/TC 213, Geometrical product specifications and
verification.
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ISO/DIS 25378
Introduction
This document 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.
NOTE To facilitate the reading and the understanding of this standard it is essential to refer to ISO/TS 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 by 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) representation(s) of a given workpiece is (are) identified in
the application of measuring procedure(s).
GPS specification defines requirements through 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. 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, generically defined in this document, are well suited to
define requirements of rigid parts and assemblies and may also be applied to non-rigid parts and assemblies.
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DRAFT INTERNATIONAL STANDARD ISO/DIS 25378
Geometrical product specifications (GPS) — Specification —
Characteristics and conditions
1 Scope
This document defines general terms for geometrical specifications, characteristics and conditions. These
definitions are based on concepts developed in ISO/TS 17450-1 and ISO 22432 and they are given by using a
mathematical description based on Annex B of ISO/TS 17450-1.
This document 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 standardisation for
industry and software makers in a consistent manner.
2 Normative references
The following referenced documents are indispensable for 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 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
ISO/TS 17450-1:1999, Geometrical product specifications (GPS) — General concepts — Part 1 : Model for
geometric specification and verification
ISO/TR 14638, Geometrical product specification (GPS) – Masterplan
1)
ISO 22432 , 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/TS 17450-1, ISO 3534-1 and ISO
3534-2 and the following apply.
3.1
GPS specification
expression of a set of one or more condition(s) on one or more characteristic(s)
NOTE 1 A specification can express a combination of individual conditions on an individual characteristic or a
population condition on a population characteristic.
1)
In preparation
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ISO/DIS 25378
NOTE 2 A specification consists of one or more single specifications. These single specifications can be individual
specifications, population specifications or any combination.
3.1.1
single (GPS) specification
expression of a set of one or more condition(s) on one characteristic
EXAMPLE of single specification with one condition: the local diameter evaluated on any workpiece shall be less than 10,2
(the expression of this specification can be for instance φ 10,2 max).
EXAMPLE of single specification with two conditions: the local diameter evaluated on any workpiece shall be greater than
9,8 and less than 10,2 (the expression of this specification can be for instance φ 10 ± 0,2).
EXAMPLE of single specification with two conditions : the mean of minimum circumscribed diameters taken on the
population of the workpieces shall be less than 10,1 and greater than 9,9.
3.1.1.1
individual specification
specification applicable on each workpiece
EXAMPLE of individual specification with one single specification: the local diameter evaluated on any workpiece shall be
less than 10,2 (the expression of this specification can be for instance φ 10,2 max).
EXAMPLE of individual specification with two single specifications: any local diameter evaluated on any workpiece shall
be greater than 9,8 and the minimum circumscribed diameter shall be less than 10,2 (the expression of this specification
can be for instance for a shaft φ 10 ± 0,2 Ⓔ).
3.1.1.2
population specification
specification applicable to a set of the population of workpieces
NOTE a population specification consists of a set of one or more single specifications
EXAMPLE of population specification with two conditions : the mean of minimum circumscribed diameters taken on the
population of the workpieces shall be less than 100,1 and greater than 99,9.
3.2
condition
combination of a limit value and a binary relational mathematical operator
NOTE 1 A binary relational mathematical operator is a mathematical concept which generalise the notion as
“greater or equal to….” in arithmetics, 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 this last case the limit
value depends on the function of the ordinates of the coordinate system or graphical ordinate system.
NOTE 4 The limit value can be a 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 of condition is not the subject
of this 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)
EXAMPLE 1 "be less than or equal to 6,3", the expression of this condition can be for instance : 6,3 max or U 6,3.
Mathematically : let X be the considered value of characteristic, the condition is X ≤ 6,3
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ISO/DIS 25378
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.
Mathematically : let X be the considered value of characteristic, the condition is 0,8 ≤ X
EXAMPLE 3 a set of two complementary conditions (lower and upper limits) can be expressed through, for instance:
+0,4 +0,3
0 −0,1
10,2 – 9,8 , 9,8 , 10 ± 0,2 , or 9,9 .
Mathematically : let X be the considered value of characteristic, the condition is 9,8 ≤ X ≤ 10,2
EXAMPLE 4 “be less than or equal to R, R being given by a function, R= (X² + Y²)*0,85: X and Y being the ordinates
of the coordinate system.
3.2.1
individual condition
condition where the limit value applies to any value of an individual characteristic coming from any workpiece
NOTE an individual condition can be used alone or in combination with a population condition on the corresponding
population characteristic.
EXAMPLE of individual condition used in an individual specification: the individual characteristic value shall be less than or
equal to 10,2.
Mathematically : let X be the considered value of individual characteristic, the condition is X ≤ 10,2
3.2.2
population condition
condition where the limits apply to the value of population characteristic coming from of the population of
values of individual characteristic taken on the workpieces.
NOTE the population condition can be used for example, for statistical process control (SPC).
EXAMPLE of 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 population characteristic (mean value of the population of global
individual characteristic values), the condition is X ≤ 10,1
3.3
geometrical characteristic
individual characteristic or population characteristic
NOTE 1 A characteristic could be geometrical, optical, mechanical, chemical, etc.
NOTE 2 This standard applies to the field of geometry and therefore, throughout this document, only "geometrical
characteristics" are used. Characteristic is defined in ISO 9000.
NOTE 3 The geometrical characteristic permits the evaluation of a quantity which could be associated to, for instance
an angular dimension, a linear dimension, a square dimension, a volume dimension, etc.
3.3.1
individual (geometrical) characteristic
single geometrical property of one or more feature(s)
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 qualified by
local individual characteristic or global individual characteristic).
EXAMPLE The two points 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 individual characteristic.
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ISO/DIS 25378
3.3.1.1
local individual characteristic
individual characteristic whose result of evaluation is not unique
NOTE A local individual characteristic is evaluated on portion feature(s) and can be a single characteristic or a
calculated characteristic.
EXAMPLE 1 The two points diameter is an individual characteristic and the result is mathematically varying along the
cylindrical feature: it is a local individual characteristic.
EXAMPLE 2 see 5.1.2
3.3.1.2
global individual characteristic
individual characteristic whose result of evaluation is 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 local individual characteristic, called respectively qualified single and calculated.
EXAMPLE 1 The minimum circumscribed cylinder diameter is a global individual characteristic (the result is
mathematically unique).
EXAMPLE 2 The maximum of two points diameters along a given cylinder is a global individual characteristic (the
result coming from a statistic and is mathematically unique).
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 workpieces
EXAMPLE 1 The arithmetic mean or the standard deviation on the population of workpieces, of a global individual
characteristic are population characteristics.
NOTE 2 Population characteristics are only statistically meaningful when the value is the result of global individual
characteristics .
EXAMPLE 2 The minimum circumscribed cylinder diameter has one unique value for a given cylindrical feature.
Therefore a population characteristic based on this individual characteristic value will be statistically meaningful. The 2-
point diameter for a given cylindrical feature will vary within a range, dependent upon the form deviations of the feature. In
this case, a population characteristic can not be defined from the population of values. It could be possible in this case to
establish a population characteristic from the maximum value of two point diameter along the feature. In this case the
individual characteristic is a global individual characteristic which is the maximum two point diameter on a given workpiece.
NOTE 3 The population characteristic can be used for example, for statistical process control (SPC).
3.4
statistic
completely specified function of random variables
[ISO 3534-1:2006, 1.8]
NOTE 1 In GPS, the random variables, which are used are in most of cases one-dimensional (scalar). Multi-
dimensional (vector) variables also exist.
NOTE 2 For a population or a sample of individual characteristic values, at least one statistic can be applied. In GPS,
statistic can be used on a population of local individual characteristic values taken on one workpiece or, on a population of
global individual characteristic values taken on a population of workpieces.
The statistic can, for example, be one listed in Table 1.
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ISO/DIS 25378
EXAMPLE See Table 1. More information can be found in the ISO 3534 series of standards.
Table 1 — Non exhaustive list of statistics
a)
Description of the statistic Mathematical description according to ISO 3534-1
A) the minimum, minimum (X)
B) the maximum, maximum (X)
n
C) the expected value (mean),
1
k k
μ = E(X ) = X ,
∑ i
n
i=1
or μ = E[g(X )] = g(X )dp = g(x)dF(x)
∫ ∫
D) the difference between the average and the target µ −TV
value (TV),
E) the standard deviation,
σ = V (X )
2
F) the variance,
V (X ) = E[X −E(X )]
a
Where X is the characteristic value
NOTE 3 For some statistical applications (like SPC), it may be necessary to define a "Target Value" (see ISO
7966:1993 and ISO 3534-2:2002).
3.5
calculated characteristic
local or global individual characteristic obtained from a collection of a set of values of one local individual
characteristic by using a function
EXAMPLE 1 The normal vector obtained from three local individual characteristic vector values is a calculated
characteristic, which is a local individual characteristic (see Figure 1)
EXAMPLE 2 The expected value (mean value) obtained from the population of values of local diameter of the cylinder
in a specific section is a local individual characteristic.
EXAMPLE 3 The expected value (mean value) obtained from the population of values of local diameter of the cylinder
(taking into account all section) is a global individual characteristic.
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ISO/DIS 25378
Z
R
3
V
i
R
2
R
1
X
C
i
Y
Key
R1, R2, R3 values of a local individual characteristic in a coordinate system
C coordinate assign to the normal vector of a face
i
normal vector of the face
V
i
Figure 1 — Calculated characteristic at the angles of normal vector of a face coming from three
values of a local individual characteristic
3.6
combination characteristic
geometrical characteristic obtained from a collection of values relative to a set of geometrical characteristics
by using a function
EXAMPLE The volume of a cylinder can be seen like a combination characteristic which is a function of two
geometrical characteristic values: the length and the diameter of the cylinder
3.7
value of a geometrical characteristic
magnitude of a geometrical characteristic, quantified on a workpiece or the population of workpieces,
NOTE The value of a characteristic is in most of case a uni-dimensional value, but can be be multi-dimensional
(vector value).
3.7.1
value of an individual characteristic
magnitude of an individual characteristic, quantified on one workpiece
3.7.2
value of a population characteristic
magnitude of a population characteristic, quantified on the population of workpieces
NOTE 1 By using sampling (instead of the whole population), a sampling uncertainty is introduced (see GUM Annex
E.4).
NOTE 2 The evaluation of a population characteristic is a two-step process:
⎯ evaluation of a set of results of individual characteristic,
⎯ statistical evaluation of the results of step 1.
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ISO/DIS 25378
NOTE 3 For any individual characteristic value, the value obtained from a simplified verification operator will in general
differ from the value obtained from a perfect verification operator. In general, there is no simple way to estimate the
variation of this difference and in most practical cases it is simply impossible. It is not unusual for this difference to be of
the same magnitude as the population variation. The variation in the difference may increase or decrease the evaluated
population variation. Because this difference enters into the statistical calculation and affects it in such a significant and
unpredictable way, a meaningfu
...
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