SIST EN ISO 22432:2012
(Main)Geometrical product specifications (GPS) - Features utilized in specification and verification (ISO 22432:2011)
Geometrical product specifications (GPS) - Features utilized in specification and verification (ISO 22432:2011)
This International Standard defines general terms and types of features for geometrical features of specifications for workpieces. These definitions are based on concepts developed in ISO/TS 17450-1. This International Standard aims to serve as the “road map” mapping out the interrelationship between geometrical features, thus enabling future standardization for industry and software makers in a consistent manner.
Geometrische Produktspezifikation (GPS) - Zur Spezifikation und Prüfung benutzte Geometrieelemente (ISO 22432:2011)
Diese internationale Norm legt die allgemeinen Begriffe und Merkmalstypen von Geometrieelementen zur technischen Beschreibung von Werkstücken fest. Diese Festlegungen beruhen auf den in der Norm ISO/TS 17450 1 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 - Éléments utilisés en spécification et vérification (ISO 22432:2011)
L'ISO 22432:2011 définit les termes généraux et les types d'éléments pour les éléments géométriques des spécifications des pièces. Ces définitions s'appuient sur les concepts développés dans l'ISO/TS 17450‑1.
L'ISO 22432:2011 n'est pas destinée, en tant que telle, à un usage industriel par les concepteurs, mais vise à servir de fil d'Ariane pour l'élaboration des relations entre les éléments géométriques, permettant ainsi la future normalisation pour l'industrie et les concepteurs de logiciels de manière cohérente.
Specifikacija geometrijskih veličin izdelka - Značilnosti, potrebne za geometrijsko specifikacijo in preverjanje (ISO 22432:2011)
Ta mednarodni standard definira splošne izraze in vrste značilnosti za geometrijske značilnosti specifikacij za obdelovance. Te definicije temeljijo na konceptih, razvitih v ISO/TS 17450-1. Ta mednarodni standard naj se uporablja kot »zemljevid«, ki preslikuje medsebojne povezave med geometrijskimi značilnostmi in s tem dosledno omogoča prihodnjo standardizacijo za industrijo in izdelovalce programske opreme.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 22432:2012
01-januar-2012
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND=QDþLOQRVWLSRWUHEQH]DJHRPHWULMVNR
VSHFLILNDFLMRLQSUHYHUMDQMH ,62
Geometrical product specifications (GPS) - Features utilized in specification and
verification (ISO 22432:2011)
Geometrische Produktspezifikation (GPS) - Zur Spezifikation und Prüfung benutzte
Geometrieelemente (ISO 22432:2011)
Spécification géométrique des produits - Éléments utilisés en spécification et vérification
(ISO 22432:2011)
Ta slovenski standard je istoveten z: EN ISO 22432:2011
ICS:
17.040.40 6SHFLILNDFLMDJHRPHWULMVNLK Geometrical Product
YHOLþLQL]GHOND *36 Specification (GPS)
SIST EN ISO 22432:2012 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 22432:2012
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SIST EN ISO 22432:2012
EUROPEAN STANDARD
EN ISO 22432
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2011
ICS 17.040.01
English Version
Geometrical product specifications (GPS) - Features utilized in
specification and verification (ISO 22432:2011)
Spécification géométrique des produits (GPS) - Éléments Geometrische Produktspezifikation (GPS) - Zur
utilisés en spécification et vérification (ISO 22432:2011) Spezifikation und Prüfung benutzte Geometrieelemente
(ISO 22432:2011)
This European Standard was approved by CEN on 8 July 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-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 22432:2011: E
worldwide for CEN national Members.
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SIST EN ISO 22432:2012
EN ISO 22432:2011 (E)
Contents Page
Foreword .3
2
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SIST EN ISO 22432:2012
EN ISO 22432:2011 (E)
Foreword
This document (EN ISO 22432:2011) 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 May 2012, and conflicting national standards shall be withdrawn at the
latest by May 2012.
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 22432:2011 has been approved by CEN as a EN ISO 22432:2011 without any modification.
3
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SIST EN ISO 22432:2012
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SIST EN ISO 22432:2012
INTERNATIONAL ISO
STANDARD 22432
First edition
2011-11-15
Geometrical product specifications
(GPS) — Features utilized in specification
and verification
Spécification géométrique des produits (GPS) — Éléments utilisés en
spécification et vérification
Reference number
ISO 22432:2011(E)
©
ISO 2011
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2011
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2011 – All rights reserved
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
Contents Page
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Relations between the geometrical feature terms . 35
Annex A (normative) Overview diagram . 39
Annex B (informative) Examples of links between the features . 45
Annex C (informative) Relation to the GPS matrix model . 48
Bibliography . 50
© ISO 2011 – All rights reserved iii
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SIST EN ISO 22432:2012
ISO 22432:2011(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 22432 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 22432:2012
ISO 22432:2011(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 in all chains of standards in the
general GPS matrix.
The ISO/GPS Masterplan given in ISO/TR 14638 gives an overview of the ISO/GPS system of which this
document is a part. The fundamental rules of ISO/GPS given in ISO 8015 apply to this document and the
default decision rules given in ISO 14253-1 apply to specifications made in accordance with this document,
unless otherwise indicated.
Geometrical features exist in three “worlds”:
the world of nominal definition, where an ideal representation of the workpiece is defined by the designer;
the world of specification, where the designer has in mind several representations of the workpiece;
the world of verification, where one (or more) representation(s) of a given workpiece is (are) identified in
the application of measuring procedure(s).
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. This International Standard defines
standardized terminology for geometrical features principally in the world of specification and the world of
verification, to be used in communication between each world.
The features defined in this International Standard are well suited for the specification of rigid parts and
assemblies, and may also be applied to non-rigid parts and assemblies by specifying allowable variation
according to rigid solids.
© ISO 2011 – All rights reserved v
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SIST EN ISO 22432:2012
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SIST EN ISO 22432:2012
INTERNATIONAL STANDARD ISO 22432:2011(E)
Geometrical product specifications (GPS) — Features utilized in
specification and verification
1 Scope
This International Standard defines general terms and types of features for geometrical features of
specifications for workpieces. These definitions are based on concepts developed in ISO/TS 17450-1.
This International Standard aims to serve as the “road map” mapping out the interrelationship between
geometrical features, thus enabling future standardization 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 14660-1:1999, Geometrical Product Specifications (GPS) — Geometrical features — Part 1: General
terms and definitions
ISO/TS 17450-1:2005, Geometrical product specifications (GPS) — General concepts — Part 1: Model for
geometrical specification and verification
ISO/TS 17450-2:2002, Geometrical product specifications (GPS) — General concepts — Part 2: Basic tenets,
specifications, operators and uncertainties
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14660-1, ISO/TS 17450-1 and
ISO/TS 17450-2 and the following apply.
3.1
surface model
model representing the set of features limiting the virtual or the real workpiece
NOTE 1 All closed surfaces (see Figures 1 and A.1) are included.
NOTE 2 The surface model allows the definition of single features, sets of features, and/or portions of features. The
total product is modelled by a set of surface models corresponding to each workpiece.
EXAMPLE Case of a hollow surface.
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
a
Representation of a real surface of the workpiece
Representation of the real workpiece
Representation of nominal Representation of skin Representation of discrete Representation of sampled
surface model model surface model surface model
a
For the purpose of this International Standard.
NOTE It is impossible to predict the total geometry of the real workpiece due to its geometrical imperfections. In this
International Standard, a real surface of the workpiece is illustrated in solid black.
Figure 1 — Example of real surface of the workpiece and its models
3.1.1
nominal surface model
surface model of ideal geometry defined by the technical product documentation
NOTE 1 A nominal surface model is an ideal feature (See Figure 1 and Table 1).
NOTE 2 A nominal surface model is a continuous surface composed of an infinite number of points.
NOTE 3 Any feature on the nominal surface model (skin model) contains a continuous infinite number of points.
3.1.2
skin model
surface model of non-ideal geometry
NOTE 1 The skin model is a virtual model used to express the specification operator and the verification operator
considering a continuous surface (see Table 1 and ISO/TS 17450-1).
NOTE 2 A skin model is a non-ideal feature (see Figure 1).
NOTE 3 A skin model is a continuous surface consisting of an infinite number of points.
NOTE 4 Any feature on the skin model contains a continuous infinite number of points.
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
3.1.3
discrete surface model
surface model obtained from the skin model by an extraction
NOTE 1 In addition to the required points, the extraction implies an interpolation.
NOTE 2 The discrete surface model is used to express the specification operator and the verification operator
considering a finite number of points (see Table 1).
NOTE 3 A discrete surface model is a non-ideal feature (see Figure 1).
3.1.4
sampled surface model
surface model obtained from the real workpiece model by a physical extraction
NOTE 1 In addition to the sampled points, the verification may imply an interpolation.
NOTE 2 The sampled surface model is used in verification by coordinate metrology, not, for example, in verification by
a gauge because gauging makes no measurement of points. In verification by a gauge, the real surface of the workpiece
is directly considered (see Table 1).
NOTE 3 A sampled surface model is a non-ideal feature (see Figure 1).
3.2
geometrical feature
point, line, surface, volume or a set of these previous items
NOTE 1 The non-ideal surface model is a particular geometrical feature, corresponding to the infinite set of points
defining the interface between the workpiece and the surrounding.
NOTE 2 A geometrical feature can be an ideal feature or a non-ideal feature, and can be considered as a single
feature or a compound feature.
3.2.1
nominal feature
geometrical feature of ideal geometry defined in the technical product documentation by the product designer
NOTE 1 See Figure B.1.
NOTE 2 A nominal feature is defined by the technical product documentation. See Table 1.
NOTE 3 A nominal feature can be finite or infinite; by default it is infinite.
EXAMPLE A perfect cylinder, defined in a drawing, is a nominal feature obeying a specific mathematical formula,
which is defined in a coordinate system related to the situation feature, and for which dimensional parameters are
associated. The situation feature of a cylinder is a line which is commonly called “its axis”. Taking this line as an axis of a
2 2
Cartesian coordinate system leads to writing x y D/2, D being a dimensional parameter. A cylinder is a feature of size,
of which the size is its diameter D.
3.2.2
real feature
geometrical feature corresponding to a part of the workpiece real surface
3.2.3
discrete feature
geometrical feature corresponding to a part of the discrete surface model
3.2.4
sampled feature
geometrical feature corresponding to a part of the sampled surface model
© ISO 2011 – All rights reserved 3
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
3.2.5
ideal feature
feature defined by a parameterized equation
[ISO/TS 17450-1:2005, definition 3.13]
NOTE 1 The expression of the parameterized equation depends on the type of ideal feature and on the intrinsic
characteristics.
NOTE 2 By default, an ideal feature is infinite. To change its nature, it is appropriate to specify it by the term “restricted”,
e.g. restricted ideal feature.
NOTE 3 For a complex surface defined by a cloud of points and an interpolation method, the cloud of points is
considered the parameter.
NOTE 4 This definition is also contained in ISO/TS 17450-1:2005. It is envisaged that it will be deleted from
ISO 17450-1:2011.
3.2.5.1
attribute of an ideal feature
property intrinsically attached to an ideal feature
NOTE 1 Four levels of attributes can be defined for an ideal feature: shape, dimensional parameters from which a size
can be defined in the case of a feature of size, situation feature and skeleton (when the size tends to zero).
NOTE 2 If the ideal feature is a feature of size, then one of the parameters of the shape can be considered as a size.
3.2.5.1.1
feature of size
geometrical feature having one or more intrinsic characteristics, only one of which may be considered as a
variable parameter, that additionally is a member of a “one-parameter family”, and obey the monotonic
containment property, for that parameter
NOTE 1 A feature of size can be a sphere, a circle, two straight lines, two parallel opposite planes, a cylinder, a torus,
etc. In former International Standards a wedge and a cone were considered as features of size, and a torus was not
mentioned.
NOTE 2 There are restrictions when there is more than one intrinsic characteristic (e.g. a torus).
NOTE 3 Relative to the function, a feature of size is particularly useful for the expression of material requirements
(LMR and MMR, see ISO 2692).
EXAMPLE 1 A single cylinder constituting a hole or a shaft is a feature of size. Its size is its diameter.
EXAMPLE 2 A compound feature of two single parallel plans constituting a groove or a key is a feature of size. Its size
is its width.
3.2.5.1.1.1
one-parameter family
set of ideal geometrical features defined by one or more dimensional parameters whose members are
generated by varying one parameter
EXAMPLE 1 A set of o-rings (torus-shaped) with the same fixed median-ring diameter and different cross-sectional
diameters is a one-parameter family (see Figure 2).
EXAMPLE 2 A set of gauge blocks defined by the gauge blocks' thickness is a one-parameter family.
4 © ISO 2011 – All rights reserved
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
Key
D median-ring diameter
d cross-sectional diameter
Figure 2 — Example of one-parameter family
3.2.5.1.1.2
monotonic containment property
property of a one-parameter family where a member with a given size contains any member with a smaller
size
EXAMPLE 1 A torus belonging to a one-parameter family, corresponding to a set of o-rings (torus-shaped) with the
same fixed median-ring diameter and different cross-sectional diameters, respects the monotonic containment property,
because from an ideal point of view, the larger family member completely envelopes the smaller family member (see
Figure 3).
EXAMPLE 2 A torus belonging to a one-parameter family, corresponding to a set of o-rings (torus-shaped) with
different median-ring diameters and the same fixed cross-sectional diameter, does not respect the monotonic containment
property and therefore cannot be considered as a feature of size.
Figure 3 — Monotonic containment property
3.2.5.1.2
situation feature
geometrical feature defining the location or orientation of an ideal feature and which is a geometrical attribute
of the ideal feature
See Figures 4 to 7.
© ISO 2011 – All rights reserved 5
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
a) Pair of parallel planes b) Cone c) Two non-parallel planes
Figure 4 — Example of situation planes
a) Axis of a cylinder b) Axis of a cone
Figure 5 — Example of situation lines
a) Situation point of a cone b) Situation point of a sphere
Figure 6 — Example of situation points
6 © ISO 2011 – All rights reserved
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
Figure 7 — Example of situation helix
NOTE In many cases, instead of using the situation helix, the axis of the situation helix is used.
3.2.5.2
shape of an ideal feature
mathematical generic description defining the ideal geometry of a feature
NOTE An ideal feature of a preset shape can be qualified or named.
EXAMPLE 1 Planar shape, cylindrical shape, spherical shape, conical shape.
EXAMPLE 2 A surface can be qualified “planar surface” or be directly named “plane”.
3.2.5.3
skeleton feature
reduction of an ideal feature when its size is equal to zero
NOTE In some cases, the skeleton feature is identical to the situation feature. In the case of the cylinder, the skeleton
feature is identical to the situation feature, which is not the case for the torus.
EXAMPLE In the case of a torus, there are two dimensional parameters of which one is a size (the cross-sectional
diameter of the torus). Its skeleton is a circle and its situation features are its plane and a perpendicular line.
3.2.6
non-ideal feature
imperfect feature fully dependent on the non-ideal surface model (skin model)
[ISO/TS 17450-1:2005, definition 3.19]
NOTE 1 A non-ideal feature is, by default, of finite dimension. To change this nature, it is appropriate to specify it by
associating the restricted term.
NOTE 2 This definition is also contained in ISO/TS 17450-1:2005. It is envisaged that it will be deleted from
ISO 17450-1:2011.
3.2.7
specification feature
geometrical feature identified from the skin model or from the discrete surface model and defined by the
specification operator
See Table 1 and Figure B.2.
NOTE Specification and verification operators are defined in ISO/TS 17450-2.
EXAMPLE 1 In the process of specification, an ideal cylinder identified from the skin model by an association is an
ideal specification feature.
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
EXAMPLE 2 In the process of specification, a non-ideal cylindrical surface identified from the skin model by a partition
is a non-ideal specification feature.
3.2.8
verification feature
geometrical feature (identified from the skin model, the discrete surface model or the sampled surface model)
or real feature defined by the verification operator
See Table 1 and Figure B.3
NOTE 1 In the world of verification, mathematical operations can be distinguished from physical operations. These
physical operations are based on physical procedures; they are generally mechanical, optical or electromagnetic. The
complete specification operator includes the type of physical property to which the specification applies.
NOTE 2 The geometrical feature identified from the skin model or from the discrete surface model is used to define the
verification operator. The geometrical feature identified from the sampled surface model and the real feature are used to
implement the verification operator.
EXAMPLE 1 In the process of verification, a perfect cylinder identified from the workpiece by an association is an ideal
verification feature.
EXAMPLE 2 In the process of verification, an imperfect cylindrical surface identified from the workpiece by a partition
is a non-ideal verification feature.
Table 1 — Use of surface models
Surface model
Field of use Real surface
Nominal Skin Discrete Sampled
surface model model surface model surface model
Technical product documentation Applicable Non-applicable Non-applicable Non-applicable Non-applicable
Specification operator Non-applicable Applicable Applicable Non-applicable Non-applicable
Verification operator Non-applicable Applicable Applicable Applicable Applicable
3.2.9
single feature
geometrical feature which is a single point, a single line, or a single surface
NOTE A single feature can have none, or one or more intrinsic characteristics, e.g.:
a plane is a single feature but has no intrinsic characteristic;
a cylinder has only one intrinsic characteristic;
a torus has two intrinsic characteristics.
EXAMPLE A cylinder is a single feature (see Figures 8 and 9). A set of surfaces made up of two intersecting planes
is not a single feature, because one plane has a greater invariance degree than two planes (see 3.2.9.4, Note 3).
8 © ISO 2011 – All rights reserved
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
Nominal feature Specification feature Verification feature
Single integral
features
Single associated
features
Single feature
portions
Obtained from
Nominal surface Discrete surface Sampled surface Real surface of a
Skin model
model model model workpiece
Key
1 single integral features 3 single feature portions
2 single associated features 4 single nominal features
Figure 8 — Examples of single features built from the same nominal plane
© ISO 2011 – All rights reserved 9
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
Nominal feature Specification feature Verification feature
Example of a
single nominally
planar feature
Example of a
single nominally
cylindrical feature
Example of a
single-portion
nominally planar
feature
Example of a
feature pair on a
nominally
cylindrical
surface
Obtained from
Nominal surface Discrete surface Sampled surface Real surface of a
Skin model
model model model workpiece
Figure 9 — Examples of single features built from different surface models
10 © ISO 2011 – All rights reserved
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
3.2.9.1
single point
point taken from a single surface or from a single line
3.2.9.2
single line
continuous line which is nominally a straight line, a circle or a complex line
NOTE 1 An arc is a restricted circle (see Figure 10).
NOTE 2 A single line does not intersect itself.
Figure 10 — Example of single lines
3.2.9.3
complex line
continuous line that is not a straight line or a circular line of which the shape and the extension are defined
and indicated by the designer in respect of the writing rules
3.2.9.4
single surface
continuous surface which is nominally a plane, a cylinder, a sphere, a cone, a torus, another surface of
revolute invariance class, a surface of prismatic invariance class, a helix, a surface of complex invariance
class, or a restricted part of one of them
NOTE 1 A revolute surface is a single surface if its generatrix is a single line (see Figure 11).
NOTE 2 Table 1 of ISO/TS 17450-1:2005 illustrates the types of single surfaces with their invariance degree.
NOTE 3 If a surface contains a surface portion of higher invariance degree than itself then it is not a single surface. A
partial ordering of single-surface types, based on whether they can contain each other, is given in Figure 12. The ordering
is partial because some surface types cannot be contained within each other.
Figure 11 — Example of single surfaces
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SIST EN ISO 22432:2012
ISO 22432:2011(E)
Complex
Helix Revolute Prism
Torus
Cylinder
Cone
Sphere
Plane
Figure 12 — Partial ordering of single-surface types
3.2.9.5
complex surface
continuous surface of which the shape and the extension are defined and indicated by the designer in respect
of the writing rules, and is not considered a plane, cylinder, cone, torus or sphere
3.2.10
compound feature
geometrical feature which is a collection of several single features
NOTE 1 A compound feature can have none, or one or more intrinsic characteristics. For instance, the set of two
parallel planes is a compound feature, which has one intrinsic characteristic.
NOTE 2 The number of features constituting a compound feature can be finite (countable) or infinite
...
SLOVENSKI STANDARD
oSIST prEN ISO 22432:2010
01-julij-2010
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND3RWUHEQH]QDþLOQRVWL]DJHRPHWULMVNR
VSHFLILNDFLMRLQSUHYHUMDQMH ,62',6
Geometrical product specifications (GPS) - Features utilized in specification and
verification (ISO/DIS 22432:2007)
Geometrische Produktspezifikation (GPS) - Zur Spezifikation und Prüfung benutzte
Geometrieelemente (ISO/DIS 22432:2007)
Spécification géométrique des produits - Éléments utilisés en spécification et vérification
(ISO/DIS 22432:2007)
Ta slovenski standard je istoveten z: prEN ISO 22432
ICS:
17.040.30 Merila Measuring instruments
oSIST prEN ISO 22432:2010 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
oSIST prEN ISO 22432:2010
EUROPEAN STANDARD
DRAFT
prEN ISO 22432
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2007
ICS
English Version
Geometrical product specifications (GPS) - Features utilized in
specification and verification (ISO/DIS 22432:2007)
Spécification géométrique des produits - Éléments utilisés
en spécification et vérification (ISO/DIS 22432:2007)
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 22432:2007: E
worldwide for CEN national Members.
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oSIST prEN ISO 22432:2010
prEN ISO 22432:2007 (E)
Foreword
This document (prEN ISO 22432:2007) 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 parallel Enquiry.
Endorsement notice
The text of ISO/DIS 22432:2007 has been approved by CEN as prEN ISO 22432:2007
without any modifications.
2
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oSIST prEN ISO 22432:2010
DRAFT INTERNATIONAL STANDARD ISO/DIS 22432
ISO/TC 213 Secretariat: DS
Voting begins on: Voting terminates on:
2007-03-01 2007-08-01
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
Geometrical product specifications (GPS) — Features utilized in
specification and verification
Spécification géométrique des produits — Éléments utilisés en spécification et vérification
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.
© International Organization for Standardization, 2007
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ISO/DIS 22432
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©
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ISO/DIS 22432
Contents
1 Scope .1
2 Normative references.1
3 Terms and definitions .1
Annex A (normative) Overview diagram.41
Annex B (informative) Examples of links between the features.47
B.1 Nominal features.47
B.2 Specification features .48
B.3 Verification features .49
Annex C (informative) Relation to the GPS matrix model.50
C.1 Information about this International Standard and its use .50
C.2 Position in the GPS matrix model.50
C.3 Related International Standards .50
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ISO/DIS 22432
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 22432 was prepared by Technical Committee ISO/TC 213, Dimensional and geometrical product specifications
and verification (GPS).
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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 in all chain 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 features exist in three “worlds”:
⎯ the world of nominal definition, where an ideal representation of the workpiece is defined by the designer;
⎯ the world of specification, where the designer has in mind several representations of the workpiece;
⎯ the world of verification, where a (or more) representation(s) of a given workpiece is (are) identified in the
application of measuring procedure(s).
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. ISO 22432 defines standardized
terminology for geometrical features principally in the world of specification and the world of verification.
Furthermore, it defines standardized terminology for the communication between each world.
The features defined in this document are well suited for specification of rigid parts and assemblies and may also
be applied to non-rigid parts and assemblies by specifying allowable variation according to rigid solids.
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DRAFT INTERNATIONAL STANDARD ISO/DIS 22432
Geometrical Product Specifications (GPS) — Features utilized in
specification and verification
1 Scope
This International standard defines general terms and types of features for geometrical features of specifications for
workpieces. These definitions are based on concepts developed in ISO/TS 17450-1 and they are given by using a
mathematical description based on annex B of ISO/TS 17450-1.
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 interrelationship between 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/TS 17450-1:1999, Geometrical product specifications (GPS) — General concepts — Part 1 : Model for
geometric specification and verification
ISO/DTS 16610-1, Geometrical product specifications (GPS) — Filtration — Part 1: Overview and basic concepts
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
real surface of a workpiece
[TS 17450-1]
3.2
surface model
model of the real surface of the workpiece
NOTE 1 The surface model is a closed surface representing the complete interface of the workpiece with its environment
(see Figures 1 and A.1)
NOTE 2 The surface model allows the definition of single features, sets of features, and/or portions of features. The total
product is modelled by a set of surface models corresponding to every workpiece.
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1
Picture of a real
surface of the
workpiece
2
2 2
2
Surface model a) nominal surface c) discrete surface d) sampled surface
b) skin model
model model model
Key
1 representation of the real workpiece for the purpose of this standard
NOTE It is impossible to predict the total geometry of the real workpiece due to its geometrical imperfections. In this
document, a real surface of the workpiece is illustrated in solid black.
2 Representation of models of the real surface of a workpiece.
Figure 1 — Example of real surface of workpiece and its models
3.2.1
nominal surface model
surface model of ideal geometry defined by the technical product documentation
NOTE 1 A nominal surface model is an ideal feature (See Figure 1 and Table 1)
NOTE 2 A nominal surface model is a continuous surface constituted by an infinite number of points.
3.2.2
skin model
surface model of non-ideal geometry.
NOTE 1 The skin model is a virtual model used to express the specification operator and the verification operator
considering a continuous surface (See Table 1 and ISO/TS 17450-1).
NOTE 2 A skin model is a non-ideal feature (See Figure 1).
NOTE 3 A skin model is a continuous surface constituted by an infinite number of points.
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NOTE 4 The nesting index (See ISO/DTS 16610-1) of the skin model is equal to zero
3.2.3
discrete surface model
surface model obtained from the skin model by an extraction
NOTE 1 In addition to the required points, the extraction implies a interpolation.
NOTE 2 The discrete surface model is used to express the specification operator and the verification operator considering a
finite number of points (See Table 1).
NOTE 3 A discrete surface model is a non-ideal feature (See Figure 1).
NOTE 4 A discrete surface model is a feature constituted by a finite number of points. The higher the number of points is, the
lower the nesting index is. When the nesting index tends towards zero, the discrete surface model tends towards the skin
model.
3.2.4
sampled surface model
approximation of the discrete surface model obtained by sampling of the workpiece with measuring instruments
NOTE 1 In addition to the sampled points, the verification may imply an interpolation.
NOTE 2 The sampled surface model is used in verification by co-ordinate metrology, not, for example in verification by
gauge because there is no measurement of points. In verification by gauge, the real surface of the workpiece is directly
considered (See Table 1).
NOTE 3 A sampled surface model is a non-ideal feature (See Figure 1).
NOTE 4 A sampled surface model is a feature constituted by a finite number of points. The lower the number of points is, the
higher the nesting index is.
3.3
geometric entity
entity consisting of a finite or infinite set of points
NOTE 1 A geometric entity can represent a point, a line, a surface, a volume, or a set of these previous items.
NOTE 2 The non-ideal surface model is a particular geometric entity, corresponding to the infinite set of points defining the
interface between the workpiece and the surrounding.
3.3.1
ideal feature
[ISO/TS 17450-1]
3.3.2
non-ideal feature
[ISO/TS 17450-1]
3.3.3
nominal feature
geometric entity of ideal geometry defined in the technical product documentation by the product designer.
NOTE 1 A nominal feature is defined by TPD (See Table 1).
NOTE 2 A nominal feature can be finite or infinite, by default it is infinite. When finite, it is called nominal integral feature.
NOTE 3 See B.1.
EXAMPLE a perfect cylinder defined in a drawing is a nominal feature.
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3.3.4
specification feature
geometric entity identified from the skin model or from the discrete surface model and defined by the specification
operator.
NOTE See Table 1 and B.2.
EXAMPLE 1 In the process of specification, a perfect cylinder identified from the skin model by an association is an ideal
specification feature.
EXAMPLE 2 In the process of specification, an imperfect cylindrical surface identified from the skin model by a partition is a
non-ideal specification feature
3.3.5
verification feature
geometrical entity (identified from the skin model, the discrete surface model or the sampled surface model) or real
feature defined by the verification operator
NOTE 1 See Table 1 and B.3.
NOTE 2 Geometrical entity identified from the skin model or from the discrete surface model is used to define the verification
operator. Geometrical entity identified from the sampled surface model and the real feature are used to implement the
verification operator
EXAMPLE 1 In the process of verification, a perfect cylinder identified from the workpiece by an association is an ideal
verification feature.
EXAMPLE 2 In the process of verification, an imperfect cylindrical surface identified from the workpiece by a partition is a
non-ideal verification feature.
Table 1 — Use of surface models
Surface model
Real surface
Nominal surface Skin model Discrete surface Sampled surface
model model model
TPD Non applicable Non applicable Non applicable Non applicable
Specification Non applicable Non applicable Non applicable
Operator
Verification Non applicable
Operator
3.3.6
single feature
geometric entity which is a single point, a single line, or a single surface
NOTE A single feature can have none, one or more intrinsic characteristics, e.g.:
⎯ a plane is a single feature, has no intrinsic characteristic;
⎯ a cylinder has only one intrinsic characteristic;
⎯ a torus has two intrinsic characteristics
EXAMPLE A cylinder is a single feature (See Figure 2 and Figure 3). A set of surfaces made up of two intersecting planes
is not a single feature, because one plane has a greater invariance degree than the two planes (see definition in ISO/TS 17450-
1)
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Nominal feature Specification feature Verification feature
1 : Single integral
features
1
1
1 1
2 : Single
4
associated features
1 1
1
1
2 2
2
2
3 : Single Portion
features
3
3 3 3 3
4
2 2 2 2
Obtained from
Nominal surface Skin model Discrete surface Sampled surface Real surface of a
model model model workpiece
Key
1 Single integral features.
2 Single associated features
3 Single Portion features
4 Single nominal features
Figure 2 — Example of different specification or verification single features build from a workpiece or
surface models for the same nominal plane
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Nominal feature Specification feature Verification feature
a) Example of
a single
nominally
planar
feature
b) Example of
a single
nominally
cylindrical
feature
c) Example of
a single
portion
nominally
planar
feature
d) Example of
a feature
pair on
nominally
cylindrical
surface
Obtained from
Nominal surface Skin model Discrete surface Sampled surface Real surface of a
model model model workpiece
Figure 3 — Specification or verification single feature build from a workpiece or surface models
3.3.6.1
single point
geometric entity which is an isolated point
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3.3.6.2
single line
geometric entity which on the nominal model is a continuous line where no subset exists with a number of
invariance degree greater than the invariance degree of the considered geometric entity
3.3.6.3
single surface
geometric entity which on the nominal model is a continuous surface where no subset exists with a number of
invariance degree greater than the invariance degree of the considered geometric entity and in the case of a
surface of revolute invariance class, where its generatrix is a single line
NOTE 1 A single surface can be an infinite single surface or a finite single surface (truncated). In a geometrical point of view,
a single surface is infinite (eg a cylinder has no limit, its surface is infinite), in practice a single surface is often considered as
limited (eg a cylinder can be considered as limited with a finite length)
NOTE 2 Where the generatrix intersects the axis of revolution:
⎯ once, each side of the generatrix intersection is considered as a separate single surface (see Figure 4)
⎯ twice or more, the surface between adjacent intersections is considered as a single surface (see Figure 5)
5 4
2
3
1
key
1 Generatrix
2 Axis of revolution
3 intersection point
4 Single surface relative to a cone side right
5 Single surface relative to a cone side left
Figure 4 — Example of feature of type cone (where the generatrix intersects once the axis, in this case it
exists two single features.
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5
4 6
2
1
3
key
1 Generatrix
2 Axis of revolution
3 intersection point
4 Single surface relative to a complex surface side left
5 Single surface relative to a complex surface middle
6 Single surface relative to a complex surface side right
Figure 5 — Example of surface of type revolute (where the generatrix intersects twice the axis, in this case
it exists three single features).
3.3.7
compound feature
geometric entity which is a collection of features
NOTE 1 A compound feature can have none, one or more intrinsic characteristics. For instance, the set of two parallel
planes is a compound feature, which has one intrinsic characteristic.
NOTE 2 The number of features constituting a compound feature can be finite (countable) or infinite (continuous) in number
(See Figure 7).
EXAMPLE A set of surfaces constituted by two parallel cylinders is a compound feature (See Figure 6)
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Nominal feature Specification feature Verification feature
a) Example of a
compound
feature
consisting of
two nominally
planar
surfaces
b) Example of a
compound
feature
consisting of
two nominally
cylindrical
surfaces
c) Example of
compound
feature
consisting of
a finite
number of
point pairs
Obtained from
Nominal surface Skin model Discrete surface Sampled surface Real surface of a
model model model workpiece
Figure 6 — Specification or verification compound feature built from a workpiece or surface models
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Nominal feature Specification feature Verification feature
a) Example of a
compound
feature
constituted
by a finite
number of
single portion
nominally
planar
features
b) Example of a
compound
feature
constituted
by an infinite
number of
single
nominally
straight lines
Obtained from
Nominal surface Skin model Discrete surface Sampled surface Real surface of a
model model model workpiece
Figure 7 — Example of compound feature built from a finite or infinite single features
3.3.8
feature of size
geometric entity having one or more intrinsic characteristics, only one of which may be considered as a variable
parameter, that additionally has to satisfy the following conditions:
⎯ be a member of a “one-parameter family”,
⎯ obey the monotonic containment property, for that parameter
NOTE 1 A feature of size can be a sphere, a wedge, a cone, two parallel opposite planes, a cylinder, a torus, ….
NOTE 2 There are restrictions when there are more than one intrinsic characteristics (e.g. torus).
NOTE 3 Relative to the function, feature of size is particularly useful for the expression of material requirements (LMR and
MMR).
EXAMPLE 1 A hole or a shaft is a feature of size. Its size is its diameter
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EXAMPLE 2 A slot or a key is a feature of size. Its size is its width
3.3.8.1
one-parameter family
set of ideal geometric entities defined by one or more parameters whose members are generated by varying only
one parameter
EXAMPLE A set of o-rings (torus-shaped) with the same fixed median ring diameter and different cross-section diameters
is a one-parameter family.(See Figure 8)
D
d
Key
D median ring diameter
d cross section diameter
Figure 8 — Example of parameters of feature
3.3.8.2
monotonic containment property
property of a one parameter family where a member with a given size contains any member with a smaller size
Example of the torus taken as a feature of size:
EXAMPLE 1 A torus belonging to a one-parameter family, corresponding to the set of o-rings (torus-shaped) with the same
fixed median ring diameter and different cross-section diameters, respects the monotonic containment property, because in an
ideal point of view, the larger family member completely envelopes the smaller family member (See Figure 9)
Figure 9 — Monotonic containment property
EXAMPLE 2 A torus belonging to a one-parameter family, corresponding to the set of o-rings (torus-shaped) with different
median ring diameters and the same fixed cross-section diameter, does not respect the monotonic containment property.
3.4
integral feature
geometric entity, which is part of a surface model
NOTE 1 For the statement of specifications, features obtained from partition of the surface model must be defined. These
features are models of the different physical parts of the workpiece that have specific functions, especially contact with the
adjacent workpieces. These features are called "integral features".
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NOTE 2 The integral feature is either a single or compound feature. (See Figure 10)
NOTE 3 Each integral feature corresponds to a nominal integral feature.
NOTE 4 An integral feature is identified either:
⎯ by a partition of the surface model or,
⎯ by a partition of another integral feature or,
⎯ by a collection of other integral features.
NOTE 6 See Annex A and Figure A.3.
12 © ISO 200
...
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