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ISO/CD 1302(E) ISO 1997 - All rights reserved

ii

Contents

Page

1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Normative references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Graphical symbols for the indication of surface texture . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Indication of surface texture requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Interpretation of indications of surface texture

requirements and their values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

7 Indication on drawings and other technical product documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

AnnexesA Proportions and dimensions of graphical symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21B Synoptic tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23C Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26D Necessary indications in order to ensure unambiguous

control of surface functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29E Exhaustive explanation on consequences of the new

ISO surface texture standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32F Relation to the GPS matrix model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34G Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Copyright notice

This ISO document is a working draft and is copyright protected by ISO. While the reproductionof working drafts or committee drafts in any form for use by participants in the ISO standardsdevelopment process is permitted without prior permission from ISO, neither this document nor any extract from it may be reproduced, stored or transmitted in any form for any other purposewithout written permission from ISO.

Requests for permission to reproduce this document for the purpose of selling it should beaddressed as shown below or to ISO's member body in the country of the requester:

Secretariat of ISO/TC 10/SC 1 Norsk TeknologistandardiseringOscars gate 20, Postboks 7072,N-0306 Oslo, Norway

Att.: Mr. Jan F. UlvsTel. +47 22 59 67 30FAX +47 22 59 67 33e-mail: [email protected]

Secretariat of ISO/TC 213 Danish Standards AssociationKollegievej 6, DK-2920 Charlottenlund,Denmark

Att.: Mr. Hans Henrik Kster Tel. +45 39 96 61 01Fax +45 39 96 61 02e-mail: [email protected]

Reproduction for sales purposes may be subject to royalty payments or a licensing agreement.

Violators may be prosecuted.

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ISO 1997 - All rights reserved ISO/CD 1302(E)

iii

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standardsbodies (ISO member bodies). The work of preparing International Standards is normally carried outthrough ISO technical committees. Each member body interested in a subject for which a technicalcommittee has been established has the right to be represented on that committee. Internationalorganizations, governmental or non-governmental, in liaison with ISO, also take part in the work. ISOcollaborates 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, Part3.

Draft International Standards adopted by the technical committees are circulated to the member bodiesfor voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote

ISO 1302 was prepared jointly by the Technical Committee ISO/TC 10 Technical drawings, product definition and related documentation , SC 1 Basic conventions and ISO/TC 213, Dimensional and geometrical product specifications and verification .

This International standard cancels and replaces ISO 1302:1994 of which it constitutes a technicalrevision.

Annex A forms an integral part of this International Standard.

Annexes B, C, D, E, F and G are for information only.

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iv

Introduction

This International Standard is a geometrical product specification (GPS) standard and is to be regardedas a general GPS standard (see ISO/TR 14638). It influences link 1 of the chain of standards onroughness profile, waviness profile and primary profile.

For more detailed information of the relation of this standard to other standards and the GPS matrixmodel see annex F.

[TO BE FINALIZED]

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1 Under revision

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Committee Draft ISO 1997 - All rights reserved ISO/CD 1302(E)

Geometrical product specifications (GPS) Indicationof surface texture

1 Scope

This International Standard specifies the rules for the indication of surface texture in technical productdocumentation (e.g. drawings, specifications, contracts, reports) by means of graphical symbols andtextual indications.

It facilitates the possibilities of expressing requirements for surfaces by means of:

- profile parameters related to the R-profile (roughness parameters), the W -profile (waviness parameters)and the P -profile (structural parameters) according to ISO 4287;

- motif parameters (roughness motif and waviness motif) according to ISO 12085;

- parameters related to the material ratio curve according to ISO 13565-2 and ISO 13565-3.

For the indication of requirements for surface imperfections (pores, scratches etc.), which cannot be specifiedusing surface texture parameters, reference is made to ISO 8785 which covers surface imperfections.

This International Standard does not provide rules for the choice of surface texture parameters or values of surface texture parameters.

2 Normative references

The following standards contain provisions which, through reference in this text, constitute provisions of thisInternational Standard. At the time of publication, the editions indicated were valid. All standards are subjectto revision, and parties to agreements based on this International Standard are encouraged to investigate thepossibility of applying the most recent editions of the standard indicated below. Members of IEC and ISOmaintain registers of currently valid International Standards.

ISO 129:1985, Technical drawings Dimensioning General principles, definitions, methods of executionand special indications 1

ISO 1456:1988, Electrodeposited coatings of nickel plus chromium and of copper plus nickel plus chromium

ISO 3274:1996, Geometrical Product Specifications (GPS) Surface texture: Profile method Nominal

characteristics of contact stylus instruments

ISO 3461-2:1987, General principles for the creation of graphical symbols Part 2: Graphical symbols for use in technical product documentation

ISO 4287:1997, Geometrical product specifications (GPS) Surface texture: Profile method Terms,definitions and surface texture parameters

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2 Under preparation

3 Under revision

2

ISO 4288:1996, Geometrical product specifications (GPS) Surface texture: Profile method Rules andthe procedures for the assessment of surface texture

ISO 8785:, Geometrical product specifications (GPS) Surface imperfections Terms, definitions andparameters 2

ISO 1101:1983, Technical drawings - Geometrical tolerancing - Tolerancing of form, orientation, locationand run-out - Generalities, definitions, symbols, indications on drawings 3

ISO 10135:1994, Technical drawings - Simplified representation of moulded, cast and forged parts 3

ISO 10209-1:1992, Technical product documentation Vocabulary Part 1: Terms relating to technicaldrawings: general and types of drawings

ISO 11562:1996, Geometrical Product Specifications (GPS) Surface texture: Profile method Metrological characteristics of phase correct filters

ISO 12085:1996, Geometrical product specifications (GPS) Surface texture: Profile method Motif parameters

ISO 13565-1:1996, Geometrical Product Specifications (GPS) Surface texture: Profile method; Surfaceshaving stratified functional properties Part 1: Filtering and general measurement conditions

ISO 13565-2:1996, Geometrical Product Specifications (GPS) Surface texture: Profile method; Surfaceshaving stratified functional properties Part 2: Height Characterization using the linear material ratio curve

ISO 13565-3:, Geometrical Product Specifications (GPS) Surface texture: Profile method; Surfaceshaving stratified functional properties Part 3: Height Characterization using the material probability curve 2

ISO 14253-1:, Geometrical Product Specifications (GPS) Inspection by measurement of workpiecesand measuring equipment Part 1: Decision rules for proving conformance or non-conformance withspecification 2

ISO 14660-1:, Geometrical Product Specifications (GPS) - Geometric features Part 1: General termsand definitions 2

3 Definitions

For the purpose of this International Standard, the terms and definitions given in ISO 3274, ISO 4287, ISO

4288, ISO 10209-1, ISO 11562, ISO 14660-1 and the following apply.3.1fundamental graphical symbol (for surface texture)graphical symbol indicating that a requirement for surface texture exists

NOTE - See figure 1.

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3.2basic graphical symbol (for surface texture)expanded basic graphical symbol indicating that material is to be either removed or not removed in order to

obtain the specific surface texture

NOTE - See figures 2 and 3.

3.3complete graphical symbol (for surface texture)fundamental or basic graphical symbol expanded in order to facilitate the addition of complementary surfacetexture requirements

3.4surface (texture) parameter parameter expressing a micro geometrical property of a surface

3.5(surface) parameter symbolsymbol indicating the type of surface texture parameter

NOTE - The parameter symbols are consisting of letters and numerical values e.g.: Ra, Ramax, Wz,Wz1max, AR, Rpk, Rpq , etc.

4 Graphical symbols for the indication of surface texture

Requirements for surface texture are indicated on technical drawings by several variants of graphical symbolseach having their significant meaning. These graphical symbols shall usually be supplemented with

complementary surface texture requirements in the form of numerical values and text (see 5), but it shall berecognized that the graphical symbols used alone in some instances can have a special meaning on thetechnical drawing (see 7).

4.1 Fundamental graphical symbols for surface texture

The fundamental graphical symbols consist of two straight lines of unequal length inclined at approximately 60 E

to the line representing the considered surface, as shown in figure 1. The fundamental graphical symbol onfigure 1 used alone (without complementary information) are not a requirement.

Figure 1: Fundamental graphical symbol for surface texture

If the fundamental graphical symbol is used with complementary supplementing information (see 5), then nodecision is taken as to whether removal of material is necessary for obtaining the specified surface (see 4.2),or whether it is not allowed to remove material for obtaining the specified surface (see 4.3).

4.2 Basic graphical symbol for removal of material

If removal of material by machining is required for obtaining the specified surface, a bar shall be added to thefundamental graphical symbol, as shown i figure 2. The basic graphical symbol on figure 2 used alone (withoutcomplementary information) are not a requirement.

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Figure 2: Basic graphical symbol indicating that removal of material is required

4.3 Basic graphical symbol when removal of material is not permitted

If removal of material is not permitted for obtaining the specified surface, a circle shall be added to thefundamental graphical symbol, as shown in figure 3. For special use of this basic graphical symbol see 6.

Figure 3: Basic graphical symbol when removal of material is not permitted

4.4 Complete graphical symbol

When complementary requirements for surface texture characteristics have to be indicated (see clause 5), aline is added to the longer arm of any of the graphical symbols illustrated in figures 1 to 3, as shown in figure4.

a) any manufacturing processpermitted; b) material shall be removed; c) removal of material not permitted

Figure 4: Complete graphical symbol

4.5 Graphical symbol for "all surfaces around a workpiece outline"

When the same surface texture is required on all surfaces around a workpiece (integral features), representedon the drawing by a closed outline of the workpiece, a circle is added to the complete graphical symbolillustrated in figure 4, as shown in figure 5.

NOTE: The outline on the drawing represent the six surfaces shown on the 3D-representation of the workpiece

Figure 5: Example of a surface texture requirement applying to all (six) surfaces representedby the outline on the drawing

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4.6 Graphical symbolization for surface texture requirement for any surface

When the same surface texture is required on any surface of a workpiece (integral features) on a technicaldrawing, a circle is added to the complete graphical symbol illustrated in figure 4, and the symbol shall be

placed near the title block of the drawing, as shown in figure 6.

Figure 6: Surface texture requirement applies to any surface of the workpiece

5 Indication of surface texture requirements

In order to ensure unambiguity of a surface texture requirement in relation to the function of the particular surface, it is always necessary, in addition to the indication of both a surface texture parameter and therequirement(s) for its numerical value, to indicate other requirement e.g. filter window or sampling length,manufacturing process, surface lay and its orientation and a possible machining allowances. It may benecessary to set up requirements for several different surface texture parameters in order that the surfacerequirements ensure unambiguous functional properties of the surface.

5.1 Position of complementary surface texture requirements in the complete graphicalsymbol

The positions of the various surface texture requirements in the complete graphical symbol are shown in figure7 and will be detailed in the following. The use of position " x" is no longer endorsed. Only use positions " a "through " e ".

Figure 7: Positions (a - e) for the location of complementary requirements - position x isformer practice and is no longer endorsed

5.1.1 Surface texture parameter, numerical value and filter window/sampling length

Surface texture parameters, numerical values and filter window/sampling length can be located at differentpositions in the complete graphical symbol with the same meaning:

5.1.1.1 One single surface texture requirement

If only one single surface texture requirement, consisting of the surface texture parameter, the numerical valueand the filter window/sampling length, is to be indicated in the complete graphical symbol, it shall be locatedin the complete graphical symbol in position " a " (figure 7):

Filter window or sampling length followed by an oblique stroke, /, followed by the surface texture parameter denomination followed by its numerical value located at position " a " (see figure 7) using one text string, e.g.

0,0025-0,8 / Rz 6,8 (see 5.2 and 5.3).

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Indication of surface texture requirement on the " x" position and filter on the " a " position (as given in former editions of ISO 1302 shall be avoided on new drawings and a surface texture requirement shall always includeboth the parameter denomination and the related numerical value of the specification limit.

Previously, it was common practice that at position " x" it was adequate to indicate only the numerical value of the specification limit, implying that this was a specification limit of the Ra parameter.

5.1.1.2 Two or more surface texture requirements

If one complete graphical symbol is used to indicate two or more surface texture requirements, it shall beindicated as follows:

The first surface texture requirement is located at position a (as stated in 5.1.1.1). The second surfacetexture requirement shall be located at position b. If a third or more requirements are to be indicated, thegraphical symbol is enlarged accordingly in the vertical direction, to make room for more lines. The positiona and b is moving upwards, when the symbol is enlarged (see 5.2 and 5.3).

Indication of surface texture requirement on the " x" position and filter on the a position (as given in former editions of ISO 1302 shall be avoided on new drawings.

5.1.2 Manufacturing method

The manufacturing method, treatment, coatings or other requirements for the manufacturing process etc. toproduce the surface, e.g. turned, ground, plated, etc. shall be located at position " c " (see figure 7), see also5.5.

5.1.3 Surface lay and orientation

The symbol of the required surface lay and the orientation, if any, of the surface lay, e.g. "=", "X", "M", etc. arelocated at position " d " (see figure 7), see also 5.6.

5.1.4 Machining allowance

The required machining allowance is indicated as a numerical value using the unit mm at position " e" (seefigure 7), see also 5.7 and ISO 10135.

5.2 Indication of profile type, parameter type and requirements for parameter values

The parameter denomination and the associated numerical value include four items of information which areessential for the interpretation of the requirement:

- Which of the three surface profiles ( R, W or P ) is indicated- Which characteristic of the profile is indicated (see 5.2.1)- How many sampling lengths make up the evaluation length (if relevant, see 5.2.2)- How the indicated specification limit shall be interpreted (see 5.2.3).

The indication of a surface texture requirement shall therefore include both the parameter denomination andthe numerical value of the specification limit.

5.2.1 Indication of profile and parameter types

Three principal groups of surface texture parameters have been standardized for use in connection with thecomplete symbol. The definitions of the parameters can be found in ISO 4287, ISO 12085, ISO 13565-2 andISO 13565-3 respectively. Their parameter denominations are presented in tabular form below.

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NOTE - If the parameter denominations are used as indicated in this clause 5.2.1, it means that thedefault definition or the default interpretation of the specification limit ("16%-rule") is required. See 5.2.3for indication of the "max-rule" for the interpretation of the specification limit.

5.2.1.1 Profile parameters (ISO 4287)

Table 1 indicates the parameter denominations of the surface parameters defined in ISO 4287. The profileparameters in ISO 4287 are defined for three surface profiles ( R-, W - and P -profiles). Profile parameters aredefined with Gauss filtering according to ISO 11562.

Table 1: Denomination of profile parameters according to ISO 4287

Amplitude parameter Distancepara-

meters

Hybridpara-

meters

Curves and relatedparameters

top - valley mean value

R-profile parametersRoughness parameters Rp Rv Rz Rc Rt Ra Rq Rsk Rku RSm R

) q Rmr(c) R * c Rmr

W -profile parametersWaviness parameters Wp Wv Wz Wc Wt Wa Wq Wsk Wku WSm W

) q Wmr(c) W * c Wmr

P -profile parametersStructure parameters Pp Pv Pz Pc Pt Pa Pq Psk Pku PSm P

) q Pmr(c) P * c Pmr

5.2.1.2 Motif parameters (ISO 12085)

Table 2 indicates the parameter denominations of the surface parameters defined in ISO 12085. Theparameters in ISO 12085 are only defined for the R- and W -profiles.

NOTE - Attention is drawn to the fact that the R- and W -profiles in ISO 12085 are defined by means of another filtering method (motifs) than the one used for other parameter systems defined in ISO 4287, ISO13565-2 and ISO 13565-3.

Table 2: Motif parameter denominations according to ISO 12085

Parameters

Roughness profileRoughness motif parameters R Rx AR

Waviness profileWaviness motif parameters W Wx AW Wte

5.2.1.3 Parameters based on the material ratio curve - (ISO 13565-2, ISO 13565-3 and ISO 12085)

Two different parameter systems are associated with the material ratio curve.

Table 3 indicates the parameter denominations related to the linear material ratio curve. These parameters areonly defined for the R-profile. The parameters are defined by two different filtering processes, ISO 13565-1 andISO 12085 respectively.

Table 4 indicates the parameter denominations related to the probability material ratio curve (ISO 13565-3).These parameters are defined both for the R-profile and the P -profile.

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Table 3: Denominations of parameters based on the linear material ratio curve

Parameters

Roughness profile parameters according to ISO 13565-2Filtering according to ISO 13565-1 Rk Rpk Rvk Mr1 Mr2

Roughness profile parameters according to ISO 13565-2Filtering according to ISO 12085 Rke Rpke Rvke Mr1e Mr2e

according to ISO 13565-2 and ISO 12085.

Table 4: Denominations of parameters based on the probability material ratio curveaccording to ISO 13565-3

Parameters

Roughness profiles

Filtering according to ISO 13565-1 Rpq Rvq Rmq

Structure profilesFiltering 8 s Ppq Pvq Pmq

5.2.2 Evaluation length - number of sampling lengths within the evaluation length - ln

The surface texture requirement on the drawing applies to the evaluation length. Certain parameters aredefined on the basis of the sampling length, others on the basis of the evaluation length (See ISO 4287, ISO12085, ISO 13565-2 and ISO 13565-3). When the parameter is defined on the basis of the sampling length,the number of sampling lengths constituting the evaluation length is of decisive importance. For samplinglengths, see 5.3.

If the parameter denomination is indicated as shown in 5.2.1, it means that the requirement is the defaultevaluation length, if it is defined in the pertinent standards.

NOTE - In those cases where no default definition exists for the number of sampling lengths within theevaluation length, it is necessary to include the number of sampling lengths in the parameter denominationin order to obtain an unambiguous surface texture requirement.


The default evaluation lengths for the profile parameters defined in ISO 4287, are defined in ISO 4288:

R -profile - The default evaluation lengths of the roughness parameters are defined in 4.4 of ISO 4288, and7. The default evaluation length, ln , consists of five sampling lengths, lr :

ln = 5 lr

This means that the parameter denominations of Rp, Rv, Rz, Rc, Rt, Ra, ..., RSm, ... , as shown in table 1indicate that the evaluation length is equal to five sampling lengths.

If the number of sampling lengths within the evaluation length is to differ from the default number of five, it shallbe indicated in the symbol.

If e.g. the evaluation length is to consist of three sampling lengths, the following symbol is used:

Rp3, Rv3, Rz3, Rc3, Rt3, Ra3, ..., RSm3, ...

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4 The number of default evaluation lengths for waviness parameters is under consideration by ISO/TC 213.

5 Under consideration in ISO/TC 213.

9

W -profile - Waviness parameters. At present, no standardized default evaluation lengths exist for the wavinessparameters 4.

The number of sampling lengths shall always be included in the parameter denomination of waviness in order to obtain an unambiguous surface texture requirement, e.g. Wz5, Wa3 , etc.

P -profile - Structure parameters. The default evaluation length for structure parameters is defined in 4.4 of ISO 4288 as the entire length of the feature.

NOTE - The sampling length concept is not relevant in connection with P parameters. Consequently,indication of the number of sampling lengths in the parameter denomination of structure parameters is notrelevant.


The default evaluation lengths of motif parameters are given in 5.2 of ISO 12085 and are indicated to be 16mm.

NOTE - Attention is drawn to the fact that the evaluation length concept in the case of motif parametershas another meaning that of other surface texture parameters in that the sampling length concept does notexist. Consequently, indication of the number of sampling lengths in the parameter denomination of motif parameters is not relevant.

It has not yet been established how motif parameters with another evaluation length than the default evaluationlength are to be indicated in the complete symbol 5.

5.2.2.3 Parameters based on the material ratio curve - (ISO 13565-2, ISO 13565-3)

R -profile - The default evaluation lengths for R parameters related to the material ratio curve are defined in7 of ISO 13565-1 to be five sampling lengths:

ln = 5 lr

This means that the parameter denominations of Rk, Rpk, Rvk, Rpq, Rvq, Rmq as shown in tables 3 and 4indicates that the evaluation length is equal to five sampling lengths.

If the number of sampling lengths within the evaluation length is to differ from the default number of five, it shallbe indicated in the symbol.

If e.g. the evaluation length is to consist of eight sampling lengths, the following symbol is used:

Rk8, Rpk8, Rvk8, Rpq8, Rvq8, Rmq8

NOTE - For the parameters Rke, Rpke, Rvke , etc., the same comments as above for the motif parametersapply.

P -profile - The default evaluation length of P -profile parameters is defined in 4.4 of ISO 4288 as the entirelength of the feature.

NOTE - The sampling length concept is not relevant in connection with P parameters. Consequently,indication of the number of sampling lengths in the parameter denomination of structure parameters is notrelevant.

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5.2.3 Tolerance limits for numerical values of surface texture parameters

Two different ways exist of interpreting the specification limits of surface texture, the "16% rule" and the "max-rule" respectively; see 5.2 and 5.3 of ISO 4288 respectively.

NOTE - The "16%-rule" is defined as the default rule for all indications of surface texture requirements. Thismeans that the "16%-rule" applies to a surface texture requirement when the parameter denomination asshown in 5.2.1 is applied (see figure 8). If the max rule is to apply to a surface texture requirement, "max"is added to the parameter (see figure 9).


The "16%-rule" and the "max-rule" are both applicable to the profile parameters defined in ISO 4287.

a) in text b) in drawings

Figure 8: Parameter denomination where the 16% rule applies (default filter window)


Figure 9: Parameter denomination where the max rule applies (default filter window)


The motif parameters are defined using only the "16%-rule" (see 5.4 of ISO 12085).

5.2.3.3 Parameters based on the material ratio curve - (ISO 13565-2, ISO 13565-3)

The "16%-rule" as well as the "max-rule" apply to all parameters related to the material ratio curve defined inISO 13565-2 and ISO 13565-3.

5.3 Indication of filter window and sampling length for the parameter

As a main rule, surface texture is defined in a filter window - the wavelength range between two defined filters(see ISO 3274 and ISO 11562). This means that the filter window is the wavelength range which is includedin the evaluation. The filter window is limited by one filter which cuts off short wavelengths (short wave filter)and by another filter which cuts off long wavelengths of the surface (long wave filter). The filters arecharacterized by the so-called cut-off value. The filters and their transmission characteristics are defined in ISO11562. For motif parameters, an additional, special form of filtering is used (see 5.3.2).

NOTE - The cut-off value of the long wave filter is also designated the sampling length.

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Where no filter window is indicated in connection with the parameter denomination, the default filter windowapplies to the surface texture requirement (see 5.3.1, 5.3.2 and 5.3.3 for the definition of default filter windows).

See e.g. the surface texture requirements in figures 8 and 9 where no filter window is indicated.

NOTES 1 Certain surface texture parameters do not have a defined default filter window or a defaultshort wave filter or a default sampling length (long wave filter). In these cases the surfacetexture indication shall specify filter window, short wave filter or long wave filter to ensure thatthe surface texture requirement is unambiguous.

2 To provide assurance that the surface is controlled unambiguously by the surface texturerequirement, the filter window shall be indicated in connection with the parameter denomination in all cases.

The filter window is indicated by indicating the cut-off values of the filters (in millimeters), separated by ahyphen ("-"). The short wave filter is indicated first, the long wave filter being indicated second. See figure 10.


Figure 10: Indication of filter window in connection with a surface texture requirement

In some cases it may be relevant to indicate only one of the two filters in the filter window. The second filter then has its default value, if it exists. If only one filter is indicated, the hyphen is maintained to indicate whether the indication is of the short wave or the long wave filter, e.g. 0,008- (short wave filter indication) or -0,25 (longwave filter indication).

5.3.1 Profile parameters (ISO 4287)

5.3.1.1 R -profile - Roughness parameters

The cut-off value designations of the R-profile filter window is 8 s (short wave filter) and 8 c, the sampling length(long wave filter).

Default filter windows of the roughness parameters are defined in combination by 7 of ISO 4288 and 4.4 of ISO3274. ISO 4288 defines the default long wave filter 8 c, ISO 3274 defining the default short wave filter 8 s related

to8

c.In the event of the filter window being indicated, it may only be necessary to indicate the long wave filter 8 c,e.g. -0,8. The short wave filter 8 s will then be as specified in 4.4 of ISO 3274.

If control of both the short wave filter and the long wave filter in the filter window for roughness parameters isrequired, both shall be indicated in connection with the parameter symbol, e.g. 0,008-0,8.

5.3.1.2 W -profile - Waviness parameters

The cut-off value designations of the W -profile filter window is 8 c (short wave filter) and 8 f , the sampling length(long wave filter).

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No default values of the filter window of the W -profile is defined, nor is the ratio between 8 f and 8 c. Therefore,

the filter window shall always be indicated by both cut-off values to ensure an unambiguous requirement.

5.3.1.3 P-profile - Structure parameter

The cut-off value designations of the P -profile of the filter window is 8 c (short wave filter) and no designationof the long wave filter has been standardized ( 8 p as proposal).

No default value of the cut-off value of the short wave filter of the P -profile 8 s 4 has been defined. Therefore,the cut-off value of the short wave filter 8 s shall always be indicated to ensure an unambiguous requirement.

In the default case, P -parameters do not have any long wave filters (sampling lengths). A long wave filter (sampling length) can be indicated for P -parameters if required for the function of the workpiece.

5.3.2 Motif parameters (ISO 12085)

For motif parameters, default values of the cut-off values of the short wave filter 8 s have been defined as afunction of the applicable evaluation length (see 5.2 of ISO 12085).

NOTE - For the default evaluation length of 16 mm, 8 s = 0,008 mm

5.3.3 Parameters based on the material ratio curve - (ISO 13565-2, ISO 13565-3)

ISO 13565-1 only anticipates the use of two different sampling lengths (long wave filter) for the R-profile. Thelong wave filter having the cut-off value 8 c = 0,8 mm is the default filter having 8 s = 0,0025 mm as the relatedcut-off value of the short wave filter. Where no filter window is indicated, this filter window applies to R-

parameters related to the material ratio curve.The second standardized filter window (special definition), which is given in ISO 13565-1 as 0,008-2,5 mm, isa standard filter window specified in ISO 3274.

If P -parameters are indicated according to ISO 13565-3, the short wave filter 8 s shall be indicated in connectionwith the parameter denomination to ensure an unambiguous requirement, as there is no default definition of 8 s in this case. In the default case, P -parameters do not have any long wave filter. A long wave filter can beindicated for P -parameters if required for the function of the workpiece.

5.4 Tolerance types - unilateral or bilateral

The surface texture requirement can be indicated as unilateral or bilateral specifications. The specification limits

are expressed by indication of the parameter denomination, the parameter value and the filter window asdescribed in 5.2 and 5.3.

5.4.1 Unilateral tolerance of a surface parameter

When the parameter denomination, the parameter value and the filter window are indicated, they are to beunderstood as a unilateral upper specification limit of the parameter in question ("16%-rule" or "max-rule" limit).

If the parameter denomination, the parameter value and the filter window indicated are to be interpreted as aunilateral lower specification limit of the parameter in question (16% or max limit), then the parameter denomination shall be preceded by the letter L, e.g. L Ra 0,32.

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Figure 11: Bilateral surface specification

5.4.2 Bilateral tolerance of a surface parameter

A bilateral tolerance is indicated in the complete symbol by placing the requirement for the two tolerance limitsabove each other, the upper specification limit ("16%-rule" or "max rule" limit) preceded by U being indicatedover the lower specification limit preceded by L (see figure 11). The upper and lower specification limits arenot necessarily expressed by means of the same parameter denomination and filter window.

5.5 Indication of manufacturing method or other information regarding the method

The surface texture parameter value of an actual surface is strongly influenced by the detailed form of theprofile curve. A parameter denomination, parameter value and filter window - indicated solely as a surfacetexture requirement - do therefore not necessarily result in unambiguous function of the surface. It isconsequently necessary in almost all cases to state the manufacturing process, as this process to some extentresults in a particular detailed form of the profile curve.

There may also be other reasons for finding it appropriate to indicate the process.

a) in text b) indrawings

Figure 12: Indication of a machining process and the requirement for the roughness of the resulting surface

a) in text b)in drawings

Figure 13: Indication of a coating and the roughness requirement

The manufacturing process of the specified surface can be presented as a text and be added to the completesymbol as shown in figures 12 and 13. The coating in figure 13 is as an example indicated using the symbolicpresentation in ISO 1456. The addition to the complete symbol can be used only as information - also inaddition to the information of importance to the geometrical properties of the surface, e.g. coating thickness,coating types, etc.

NOTE - In addition to ISO 1456, ISO/TC 107, Metallic and other non-organic coatings , has issued anumber of standards dealing with issues such as methods of indication coatings.

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5.6 Indication of the surface lay

The surface lay and direction of the lay emanating from the machining process (e.g. traces left by tools) canbe indicated in the complete symbol by using the symbols shown in table 5 and illustrated by the example infigure 14. The indication of surface lay by the defined symbols is not applicable to textual indications.

Figure 14: Direction of lay of the surface pattern indicated as being perpendicular

to the drawing plane

NOTE - The direction of lay is the direction of the prevailing surface pattern which is usually determinedby the manufacturing process used.

The symbols in table 5 indicate the lay and direction of lay in relation to the drawing plane containing thesurface texture requirement.

5.7 Indication of machining allowance

The machining allowance is generally indicated only in those cases where more process stages are shown inthe same drawing. Machining allowances are therefore found e.g. in drawings of raw cast and forgedworkpieces with the final workpiece being shown in the raw workpiece. For the definition and application of

requirements for machining allowances, see ISO 10135. The indication of machining allowance by the definedsymbol is not applicable to textual indications.

Figure 15: Indicationof surface texture requirements for the "final" workpiece shown on the

casting drawing, including a requirement for a machining allowance of 3 mm

When the machining allowance is indicated, it may occur that the requirement for the machining allowance isthe only requirement added to the total or complete symbol. The machining allowance may also be indicatedin connection with a normal surface texture requirement (see figure 15).

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Table 5

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6 Interpretation of indications of surface texture requirements and their values

Surface texture requirements on a technical drawing shall as a principle consist of at least one of the symbolsshown in figures 1 to 6 and the supplementary annotations described in 5.

Graphical symbols used alone have only a meaning as a surface texture requirement when:

- used according to 7.2, or - the basic graphical symbol, shown in figure 3, is used on a drawing concerning a manufacturing process.

In this case, the interpretation is:

The spec i f ied su r face sha ll be le f t in the s ta te resu l t ing a p reced ing manufac tu r ing p rocess regard less the cond i t ion was ob ta ined by remo val o f mater ia l o r by o ther means .

Verification of whether a particular surface is in conformance or non-conformance with a given surface texturerequirement shall be in accordance to the rules and principles given in ISO 14253-1. Furthermore, theinterpretation rules of this standard and the content the relevant surface texture standards shall be taken intoaccount.

7 Indication on drawings and other technical product documentation

Surface texture requirements shall be indicated only once for a given surface and, if possible, on the same viewwhere the size and/or location are indicated and toleranced.

Unless otherwise specified, the indicated surface texture requirements are applicable for the surface after machining, coating etc. (see also Annex C).

7.1 Position and orientation of the graphical symbol and its annotation

The general rule is that the graphical symbol together with the complementary information shall be oriented

so that they can be read from the bottom or right-hand side of the drawing, in conformity with ISO 129 (seefigure 16).

Figure 16: Direction of reading of surface texture requirements

7.1.1 On an outline or by a leader line

The surface texture requirement (graphical symbol) shall touch the surface or be connected to it by means of a leader line terminating in an arrowhead.

As a general rule the graphical symbol shall, or the leader line terminating in an arrowhead, shall point at thesurface from outside the material of the workpiece either to the outline (representing the surface) or theextension of it (see figure 17 and 18).

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Figure 17: Surfacetexture requirements on the contour line that represents the surface

Figure 18: Alternative use of leader lines

7.1.2 On the dimension line in connection with the dimension of a size feature

If there is no risk of misinterpretation, the surface texture requirement may be indicated in connection with thedimensions given, as shown in figure 19.

Figure 19: Surface texturerequirement in connection with the dimension of a feature of size

7.1.3 On the tolerance frame for geometrical tolerances

The surface texture requirement may be placed on top of the tolerance frame for geometrical tolerances

(according ISO 1101), as shown in figure 20.

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Figure 20: Surface texture requirement connected to indication of geometrical tolerances

7.1.4 On extension lines

The surface texture requirement may be directly placed on extension lines or be connected to it by a leader lineterminating in an arrowhead, as shown in figures 17 and 21.

7.1.5 Cylindrical and prismatic surfaces

Cylindrical as well as prismatic surfaces need only be specified once if indicated by a centreline and if eachprismatic surface have the same surface texture requirement (see figure 21).

However, each prismatic surface needs to be indicated separately if different surface textures are required onthe individual prismatic surfaces (see figure 22).

Figure 21: Surface texture requirements on extension lines of cylindrical features

Figure 22: Surfacetexture requirements for cylindrical and prismatic surfaces

7.2 Simplified drawing indications of surface texture requirements

7.2.1 Majority of surfaces having the same surface texture requirement

If the same surface texture is required on the majority of the surfaces of a workpiece, this surface texture

requirement may be placed close to the title block of the drawing.

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This general graphical symbol corresponding to this surface texture shall be followed by:

- a basic symbol in parenthesis without any other indication (see figure 23), or - the special deviating surface texture requirement(s) in parenthesis (see figure 24).

in order to indicate that there exist other surface texture requirements that deviates from the general surfacetexture requirement.

Figure 23: Simplifiedindication when a majority of surfaces have the same required surface texture

Figure 24: Simplified indication when a majority of surfaces have the same required surfacetexture

Surface texture requirements that deviates from the general surface texture requirement is indicated directlyon the drawing in the same view of the particular surfaces in question (see figure 23 and 24).

7.2.2 Use of reference indication in case of minimal drawing space

To avoid the necessity of repeating a complicated indication a number of times, or where space is limited, asimplified reference indication may be used on the surface provided that its meaning is explained near theworkpiece in question, near the title block or in the space devoted to general notes (see figure 25).

Figure 25: Reference indication in case of minimal drawing space

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7.2.3 Special use of reference indication

If the same surface texture is required on a large number of surfaces of the workpiece, the correspondinggraphical symbol shown i figures 1, 2 or 3 may be used on the appropriate surface and its meaning given onthe drawing as shown, for example, in figures 26 to 28.

Figure 26: Simplified indication of surface texture requirements

(manufacturing process not specified)

Figure 27: Simplified indication of surface texture requirement

(removal of material)

Figure 28: Simplified indication of surface texture requirement

(removal of material not permitted)

7.3 Indication of 2 processes

If it is necessary to define surface texture both before and after treatment, this shall be explained in a note or in accordance with figure 29.

Figure 29: Indication of surface texture requirement before and after treatment(in this case coating)

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Annex A(normative)

Proportions and dimensions of graphical symbols

A.1 General requirements

In order to harmonize the size of the symbols specified in the International Standard with those of other inscriptions on technical drawings (dimensions, geometrical tolerances, etc.) the rules given in ISO 3461-2 shall be applied.

A.2 Proportions

The basic graphical symbol and its complements (see 4) shall be drawn in accordance with figures A.1to A.3.

The shape of the symbols in figure A.2 c) to A.2 g) is the same as that of the corresponding capital letter in ISO 3098-1 (lettering B, vertical).

For dimensions, see A.3.

The length of the horizontal stroke of the symbol in figure A.1 b) depends on the indication associatedwith it (see 6.3 and B.3).

Important - Use of the positions " x1" and " x2" of figure A.3 shall be avoided on new technicaldrawings and be regarded as former practice. Only the positions " a " and " b " shall be used for indication of surface texture parameters, filter window and numerical parameter value.

Figure A.1

Figure A.2

NOTE - For the placing of surface texture specifications in positions " a " to "e ", see figures 7 to 15.

The height of all lettering in areas " a ", "b ", "d " and " e " of figure A.3 shall be equal to h.

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cx1

x2 a

e d b

Figure A.3

As the lettering in area c, figure A.3, may comprise capital and/or lower-case letters, the height of this area maybe greater than h to allow for tails of lower case-case letters

A.3 Dimensions

The dimensions of the graphical symbols and additional indications shall be as specified in table A.1.

Tabel A.1Dimensions in millimetres

Height of numerals and letters, h (see ISO 3098-1) 2,5 3,5 5 7 10 14 20

Line width for symbols, d' 0,25 0,35 0,5 0,7 1 1,4 2

Line width for lettering, d

Height, H 1 3,5 5 7 10 14 20 28

Height, H 2 8 11 15 21 30 42 60

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Annex B(informative)

Synoptic tables

B.1 Graphical symbols with no inscription

Reference no. Symbol Meaning

B.1.1 Fundamental graphical symbol. It may only be used in isolation whenits meaning is "the surface under consideration" or explained by a note(see 7.2).

B.1.2 Basic graphical symbol. A machining surface with no indication of other details. Used in isolation this basic graphical symbol may beused only when its meaning is "a surface to be machined".

B.1.3 Basic graphical symbol. A surface from which removal of material isprohibited. This basic graphical symbol may also be used in a drawingrelating to a manufacturing process to indicate that a surface is to beleft in the state resulting from a preceding manufacturing process,regardless whether this state was achieved by removal of material or otherwise.

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B.2 Graphical symbols with indication of surface texture

Reference no. Symbol Meaning/Explanation

B.2.1 The process is not permitted to remove material,unilateral upper specification limit, default filter window, R-profile, maximum height of roughness 0,4F m, evaluation length of 5 sampling lengths(default), "16%-rule" (default)

B.2.2 The process shall remove material, unilateral upper specification limit, default filter window, R-profile,maximum height of roughness 0,4 F m, evaluation -length of 5 sampling lengths (default), "max-rule"

B.2.3 The process shall remove material, unilateral upper specification limit, filter window 0,008-0,8 mm, R-profile, arithmetic mean deviation 3,2 F m, evaluationlength of 5 sampling lengths (default), "16%-rule"(default)

B.2.4 The process shall remove material, unilateral upper specification limit, filter window: sampling length 0,8mm ( 8 s default 0,0025 F m) according to ISO 3274,

R-profile, arithmetic mean deviation 0,2 F m,evaluation length of 3 sampling lengths (default),"16%-rule" (default)

B.2.5 The process is not permitted to remove material,double-sided upper and lower specification limits,default filter window for both limits, R-profile, upper limit: arithmetic mean deviation 3,2 F m, evaluationlength of 5 sampling lengths (default), "max-rule",lower limit: arithmetic mean deviation 0,8 F m,evaluation length of 5 sampling lengths (default),"16%-rule" (default)

B.2.6 The process shall remove material, unilateral upper specification limit, filter window 0,8 - 25 mm, W -profile, maximum height of waviness 12 F m,evaluation length of 3 sampling lengths, "16%-rule"(default)

B.2.7 The process shall remove material, unilateral upper specification limit, filter window 8 s = 0,008 mm nolong wave filter, P -profile, total profile height 25 F m,evaluation length equal workpiece length (default),"max-rule"

NOTE - Surface texture parameters, filter windows/sampling lengths and parameter values and choice of symbols are given as examples only.

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B.3 Symbols with supplementary information

(These indications may be used in combination with the appropriate graphical symbols from B.2)


B.3.1 Manufacturing method: milled (see 5.5)

B.3.2 Surface pattern: direction of lay perpendicular to theplane of projection of the view (see 5.6)

B.3.3 Surface texture requirement applies to complete closedoutline of the projection view (see 4.5)

B.3.4 Machining allowance 3 mm (see 5.7)

NOTE - The manufacturing method, surface pattern, and machining allowance are given as examples only.

B.4 Simplified symbols


B.4.1 The meaning is defined by text added to the drawing(see 7.2.1 and 7.2.2).

B.4.2

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Annex C(informative)

Examples

Referen-ce no.

Requirement Example

C.1 Surface roughness:- bilateral specification- upper specification limit Ra = 50 F m,- lower specification limit Ra = 6,3 F m;- both "16%-rule", default;- both filter window 0,008-4 mm;- evaluation length default (5 4 mm = 20 mm);- surface lay approximately circular around the centre- manufacturing process, milling

C.2 Surface roughness on all surfaces except one:

- one single, unilateral/upper specification limit- Rz = 6,3 F m;- "16%-rule", default;- default filter window (determined by ISO 4288 and ISO

3274);- default evaluation length (5 8 c);- surface lay, no requirement;- manufacturing process shall remove material

The surface with a different requirement, has a surfaceroughness:- one single, unilateral/upper specification limit;- Ra = 0,8 F m;

- "16%-rule", default;- default filter window (determined by ISO4288 and ISO 3274);

- default evaluation length (5 8 c);- surface lay, no requirement;- manufacturing process shall remove material

C.3 Surface roughness:- two, unilateral/upper specification limits

- Ra = 1,6 F m;- "16%-rule";- filter window default (ISO

4288/3274);- evaluation length default

(5 8 c);

- Rzmax = 6,3 F m;- max- rule;- filter window -2,5 mm

(ISO 3274);- evaluation length default

(5 2,5 mm);

- surface lay approximately perpendicular on theprojection plane;

- Manufacturing process, grinding

C.4 Surface roughness:- one single, unilateral/upper specification limit;- Rz = 1 F m;- "16%-rule" default;- filter window default (ISO 4288 and ISO 3274);- evaluation length default (5 8 c);

- surface lay, no requirement;- surface treatment: nickel/chromium plating;- The surface requirement are valid for all surfaces

represented by the closed outline

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Referen-ce no.

Requirement Example

27

C.5 Surface roughness:- one unilateral upper and one bilateral specification;

- unilateral Ra = 1,6 F m;

- "16%-rule";- filter window -0,8 mm ( 8 s according to ISO 3274);- evaluation length 5 0,8 = 4 mm;

- bilateral:- upper specification limit Rz = 16 F m;- lower specification limit Rz = 6,3 F m;- both: filter window -2,5 mm ( 8 s according to ISO 3274);- both: evaluation length 5 2,5 = 12,5 mm;

- surface lay, no requirement;- surface treatment: nickel/chromium plating;

C.6 Indication of surface texture and dimensioning may becombined using the same dimension line.

Surface roughness on side surfaces of keyway- one single, unilateral upper specification limit;- Ra = 6,3 F m;- "16%-rule", default (ISO 4288 and IS 3274);- evaluation length, default (5 8 c);- surface lay, no requirement;- manufacturing process shall remove material

Surface roughness on the chamfer:- one single, unilateral/upper specification limit;- Ra = 25 F m- "16%-rule", default (ISO 4288 and ISO 3274);- evaluation length, default (5 8 c);- surface lay, no requirement;- manufacturing process shall remove material

C.7 Surface texture and dimensioning may be indicated

- together on an extended dimension line, or

- separated on the respective projection line anddimension line

the three surface roughness requirements on the exampleare all:- one single, unilateral/upper specification limit;- respectively: Ra = 1,6 F m, Ra = 6,3 F m, Rz = 50 F m,- "16%-rule", default (ISO 4288 and ISO 3274);- evaluation length, default (5 8 c);- surface lay, no requirement;- manufacturing process shall remove material

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Referen-ce no.

Requirement Example

28

C.8 Indication of surface texture, dimensioning and treatment.The example is illustrating three successive manufacturingprocesses or stages

1. stage:- one single, unilateral/upper specification limit;- Rz = 1,6 F m,- "16%-rule", default (ISO 4288 and ISO 3274);- evaluation length, default (5 8 c);- surface lay, no requirement;- manufacturing process shall remove material.

2. stage:No surface texture requirement, except:- chromium plating

3. stage:- one single, unilateral/upper specification limit, only valid

for the first 50 mm of the cylinder surface;- Rz = 6,2 F m,- "16%-rule", default (ISO 4288 and ISO 3274);- evaluation length, default (5 8 c);- surface lay, no requirement;- manufacturing process grinding

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Annex D(informative)

Necessary indications in order to ensure unambiguous control of surfacefunctions

A surface texture requirement is built of several different control elements, which can be part of the indication onthe drawing or the specification given in other documents. The elements are the following (see also figure D.1):

Figure D.1: Control elements in indication of surface texture requirements on engineeringdrawings

a) Indication of upper ( U ) or lower ( L) specification limit - see 5.4 for details

b) Filter type "X". The standardized filter is the Gauss filter (ISO 11562). The former standardized filter was the2RC-filter. In the future other filter types may be standardized. In the transition period it may be convenientfor some companies to indicate the filter type on drawings. Filter type may be indicated as "Gauss" or "2RC".This is not standardized, but an indication of filter name as proposed here is unambiguous.

c) Filter window is indicated as short wave - long wave filter - see 5.3 for details

d) Profile ( R, W or P ) - see 5.2.1 for details

e) Characteristic/parameter - see 5.2.1 for details

f) Evaluation length as the number of sampling lengths - see 5.2.2 for details

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g) Interpretation of the specification limit ("16%-rule" or "max-rule") - see 5.2.3 for details

h) Limit value in micrometers

i) Type of manufacturing process - see 4.2, 4.3 and 4.4 for details

k) Surface texture lay - see 5.6 for details

m) Manufacturing process - see 5.5 for details

Experience is that all these elements are necessary to form an unambiguous relation between the surface texturerequirement and the function of the surface. It is only in very few cases that some of the elements can be omittedin an unambiguous requirement. The majority of the elements are also necessary to set the measuring instrument(b, c, d, e, f). The rest is necessary to evaluate unambiguously the result of measurement and comparison with thelimit(s) required.

In some cases it is necessary to indicate requirements for more than one surface texture parameter (profile and/or characteristic) to establish an unambiguous relation between the requirement on the drawing and the function of the surface.

Not all surface texture parameters have a strong and universal correlation with the function of a surface. Someparameters are highly specialized in relation to the type of surface and/or type of function of the surface. Two maingroups of surface texture parameters exist for use for two main types of surfaces:

- Single process surfacesSurfaces which are the result of one manufacturing process (e.g. turning, grinding, milling, plating, painting,etc.). Parameters useful for these surfaces are defined in ISO 4287 and ISO 12085. In some cases theparameters in ISO 13565-2 may be useful for single process surfaces. Parameters intended for single processsurfaces will usually not give meaningful results used on two process surfaces.

- Two process surfacesSurfaces which are the result of two manufacturing processes, and where part of the two surface textures arepresent in and influencing the function of the resulting surface (e.g. ground surfaces, which are partially lapped,superfinished or honed). The parameters for these surfaces are defined in ISO 13565-2 and ISO 13565-3.

How strong the correlation between the surface texture parameter and the function of the surface is, and whichparameters are the appropriate for the control of a special function of a surface, shall be taken from literature or known by experience.

To simplify the indication of surface texture requirements, and still maintain the unambiguity of the relation betweenindication on the drawing and the function of the surface, a number of default conditions are defined: e.g.Interpretation of the specification limit(s), filter window and evaluation length. The default definitions result in, thateven simplified surface texture indications, e.g. Ra 1,6 and Rz 6,8 have a partly unambiguous meaning. Thisprinciple about default definitions is not yet finalized for all parameters.

The individual standards comprise information about default definitions - if any. In cases where no defaultdefinitions exist, the full informations about e.g. interpretation of specification limit(s), filter window and evaluationlength, shall be given in the indication of the surface texture requirement on the drawing to make the requirementunambiguous - and meaningful.

When a default definition exist for a surface texture parameter, two possibilities exist for the indication:

1) Use the total (existing) default definitions (as given in the standards) - use only a simplified indication on thedrawing;

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2) Indicate all the possible requirements and details in the requirement on the drawing. The detailed requirementchosen on the basis of objective known relations between the surface texture requirement and the function of the surface.

Possibility number 1 have the advantage of reducing the annotations necessary and is saving space on thedrawing. On the other hand does not ensure that the choices made by the standardized default definitions aresuitable for the specific task of controlling the function of the surface.

As a general rule it is stated that:

Surfaces which are imp ortant for th e function of a workp iece, i .e. wh ere the surface texture is of c r i t ica l fo r the func t ion , poss ib i l i ty num ber 2 sha l l always be used .

Special attention shall be given to the choice of default filter window as given in ISO 4288. The rules for choosingthe default filter window may have major influence on the measured parameter value from a surface. Small - andnearly insignificant - changes in the surface may - because of the rules in ISO 4288 - result in differences in themeasured parameter value of up to 50%. This fact point to, that the filter window - or at least the sampling length -should always be stated in the symbol on the drawing, for surfaces where the surface texture are of importancefor the function of the workpiece. In such cases the default filter should never be used.

The manufacturing process and in some cases also the surface lay are of major importance for an unambiguousrelation between the surface texture requirement on the drawing and the function of the surface. Two differentmanufacturing processes usually have "surface texture scales" of there own to relate to the same function of thesurface. To obtain the same function of a surface, usually there may be a difference of more than 100% in themeasured parameter values for the two surfaces, when the surfaces are manufactured with two different processes.

One consequence of the above mentioned facts is, that the comparison of two or more surface texture parameter values only make sense, when the individual values have the same basis, e.g. filter window, evaluation length andmanufacturing process.

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Annex E(informative)

Exhaustive explanation on consequences of the new ISO surface texturestandards

This edition of ISO 1302 is developed for use together with the new editions of the surface texture standards issuedin 1996 and 1997.

The new editions of surface texture standards are ISO 3274, ISO 4287, ISO 4288, ISO 11562, ISO 12085, ISO13565-1, ISO 13565-2, ISO 13565-3 (see 2). Three new standards which are not yet issued are listed in Annex G(ISO/CD 5436-1, ISO/WD 5436-2 and ISO/CD 12179).

A special standard for surface imperfections is ISO 8785.

A number of surface texture standards are withdrawn: ISO 468, ISO 1878, ISO 1879, ISO 1880, ISO 2632-1, ISO2632-2, ISO 2632-3 and ISO 4287/2.

The new 1996 and 1997 editions of surface texture standards have resulted in many and major changes compared

with the content of the former standards issued in the 1980s. The most important changes and consequences are:

- The measuring instrument for surface texture is redefined (ISO 3274); Skidded instruments are no longer standardized. The "true" value of a surface texture parameter is defined by an absolute measuring instrument.

- New filters are defined with a different filter characteristic (ISO 11562, digital phase correct Gaussian filter). Theformer analogue 2RC filter is no longer standardized.

- Two new surface texture profiles are defined ( W - (waviness) and P-profile) additional to the already existing R-profile or roughness profile. Each of now three surface texture profiles can be the basis of nearly all surfacetexture parameters (characteristics), e.g. Ra , Wa and Pa . See especially 5.2.1, ISO 4287 and 13565-3.

- Surface texture (all three profiles) is now defined by a filter window (short wave and long wave filter) and not

only by a single "cut-off filter" (long wave filter) - see 5.3 and ISO 3274, ISO 4287 and ISO 11562.

- The typography of surface texture parameters are changed. The parameter symbol is now written on the line,e.g. Ra and Rz . The use of subscript, e.g. Ra and R z is not used any more.

- Almost all surface texture denominations and names of existing parameters are changed (ISO 4287). The former surface roughness parameter R z (Ten point height) is not standardized in ISO any more. Rz is now the symbolfor the former R y.

- Three new groups/types of surface texture parameters is defined and standardized (ISO 12085, ISO 13565-2and ISO 13565-3). These new surface texture parameters have partly their own filtering system (ISO 12085 andISO 13565-1).

- The number of parameters, which have a default definition for interpretation of specification limit(s), filtering andevaluation length, are heavily increased from the existing three ( Ra , R y and R z ). See ISO 4288, ISO 12085 andISO 13565-1. Nearly all W - and P -parameters have no default definitions.

The changes from the former standards to the new editions of 1996 and 1997 are so many and so important, thatit is problematic to evaluate "old" surface requirements according to the new standards. Companies shall makedecisions how to make the shift from old to new standards.

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One of the most important changes is the Gaussian filter instead of the 2RC-filter. The Gaussian filter have beenavailable on instruments for several years. The new filter is intended to have an effect very near to the former 2RC.This is not fully possible. Cases exist, where the Gaussian filter reduce the measured value more than 50%compared with the value from the same surface measured with 2RC-filtering. In most cases the change of filtersresult in changes of measured values much smaller (differences less than 5-10%).

In most cases the use of filter window (instead of cut-off filter only) result in a small reduction of the measured

value, especially for smooth surfaces. The advantage of the filter window is, that the uncertainty of measurement,the dependency of the tip radius and the difference between instruments of different make is heavily reduced.

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Annex F(informative)

Relation to the GPS matrix model

For full details about the GPS matrix model see ISO/TR 14638.

F.1 Information about the standard and its use

[TO BE FINALIZED]

F.2 Position in the GPS matrix model

This International standard is a general GPS standard, which influences the chain link 1 of the chain of standardson roughness profile, waviness profile and primary profile in the general GPS matrix, as graphically illustrated onfigure F.1.

FUNDA-MENTAL

GPS

STAN-DARDS

GLOBAL GPS STANDARDS

GENERAL GPS MATRIXChain link number 1 2 3 4 5 6

SizeDistanceRadiusAngleForm of line independent of datumForm of line dependent of datumForm of surface independent of datumForm of surface dependent of datumOrientationLocationCircular run-outTotal run-outDatumsRoughness profileWaviness profilePrimary profileSurface imperfectionsEdges

Figure F.1

F.3 Related standards

The related standards are those of the chains of standards indicated in figure F.1.

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Annex G(informative)

Bibliography

[1] ISO/TR 14638:1995; Geometrical Product Specifications (GPS) - Masterplan

[2] ISO 3098-1:1974; Technical drawings - Lettering - part 1: Currently used characters

[3] ISO/CD 5436-1:-, Geometrical Product Specifications (GPS) - Surface texture: Profile method Calibration - Part1: Measurement standards 6

[4] ISO/WD 5436-2:-, Geometrical Product Specifications (GPS) - Surface texture: Profile method Calibration - Part2: Soft gauges 1

[5] ISO/CD 12179; Geometrical Product Specifications (GPS) - Surface texture - Profile method - Calibration of contact (stylus) instruments 1

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