ISO/FDIS 128-2

Technical product documentation (TPD) — General principles of representation — Part 2: Basic conventions for lines

This document establishes the types of lines used in technical drawings (e.g. diagrams, plans or maps), their designations and their configurations, as well as general rules for the draughting of lines. In addition, this document specifies general rules for the representation of leader and reference lines and their components as well as for the arrangement of instructions on or at leader lines in technical documents. Annexes have been provided for specific information on mechanical, construction and shipbuilding technical drawings. For the purposes of this document the term "technical drawing" is interpreted in the broadest possible sense encompassing the total package of documentation specifying the product (workpiece, subassembly, assembly).

Documentation technique de produits (TPD) — Principes généraux de représentation — Partie 2: Conventions de base pour les traits

Le présent document établit les types de traits utilisés dans les dessins techniques (par exemple schémas, plans ou cartes), leurs désignations et leurs configurations, ainsi que les règles générales pour le tracé de traits. De plus, le présent document spécifie des règles générales pour la représentation des lignes repères et traits de référence et leurs composants, ainsi que pour la disposition des instructions sur ou aux lignes repères dans les documents techniques. Des annexes ont été prévues pour des informations spécifiques sur les dessins industriels, dessins de construction et dessins de construction navale. Pour les besoins du présent document, le terme «dessin technique» est interprété au sens le plus large possible, englobant l'ensemble de la documentation spécifiant le produit (pièce, sous-ensemble, ensemble).

General Information

• Status: Not Published
• ICS: 01.100.01 - Technical drawings in general
• Technical Committee: ISO/TC 10 - Technical product documentation
• Drafting Committee: ISO/TC 10 - Technical product documentation
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 30-May-2022
• Due Date: 30-May-2022
• Completion Date: 30-May-2022

RELATIONS

• Replaces: ISO 128-2:2020 - Technical product documentation (TPD) — General principles of representation — Part 2: Basic conventions for lines
• Effective Date: 06-Jun-2022
• Consolidates: ISO 13185-4:2020 - Intelligent transport systems — Vehicle interface for provisioning and support of ITS Services — Part 4: Unified vehicle interface protocol (UVIP) conformance test specification
• Effective Date: 06-Jun-2022

Standards Content (sample)

ISO 128-2:2022(E)
ISO TC 10/WG 19
Date: 2022-05-16
Secretariat: SIS
Technical product documentation (TPD) — General principles of representation —
Part 2: Basic conventions for lines

Documentation technique de produits (TPD) — Principes généraux de représentation —

Partie 2: Conventions de base pour les traits
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ISO/FDIS 128-2:2022(E)
FDIS stage
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ISO/FDIS 128-2:2022(E)
© ISO 2022, Published in Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or

utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,

or posting on the internet or an intranet, without prior written permission. Permission can be

requested from either ISO at the address below or ISO’s member body in the country of the

requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
[e-mail]
www.iso.org
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ISO/FDIS 128-2:2022(E)
Contents

Foreword ......................................................................................................................................................................... vi

Introduction................................................................................................................................................................. viii

1 Scope .................................................................................................................................................................... 1

2 Normative references .................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................... 2

4 Types of lines .................................................................................................................................................... 3

4.1 General ................................................................................................................................................................ 3

4.2 Basic types ......................................................................................................................................................... 4

4.3 Line subtypes .................................................................................................................................................... 5

4.4 Variations of the basic types of lines ........................................................................................................ 5

4.5 Combinations of lines with the same length .......................................................................................... 5

4.5.1 Arrangement of two or more lines parallel to each other ................................................................ 5

4.5.2 Arrangement of two different types of lines .......................................................................................... 6

4.5.3 Arrangement of two continuous lines parallel to each other with regularly recurring

connecting elements between them ......................................................................................................... 6

4.5.4 Arrangement of regularly recurring geometric pictorial elements in association with

continuous lines ............................................................................................................................................... 6

5 Line dimensions ............................................................................................................................................... 7

5.1 Line width .......................................................................................................................................................... 7

5.2 Deviation in line width .................................................................................................................................. 7

5.3 Configuration of lines ..................................................................................................................................... 7

6 Draughting of lines .......................................................................................................................................... 8

6.1 Spacing ................................................................................................................................................................ 8

6.2 Junctions ............................................................................................................................................................. 8

6.2.1 Types .................................................................................................................................................................... 8

6.2.2 Representation ................................................................................................................................................. 9

6.3 Location of a second line ............................................................................................................................ 10

6.4 Hierarchy of overlapping lines ................................................................................................................ 11

7 Colours ............................................................................................................................................................. 11

8 Designation ..................................................................................................................................................... 11

9 Basic conventions and applications for leader lines and reference lines ................................ 12

9.1 Presentation of leader lines ..................................................................................................................... 12

9.2 Representation of reference lines .......................................................................................................... 14

9.3 Indication of instructions .......................................................................................................................... 16

Annex A (informative) Preparation of lines by CAD systems ................................................................... 17

Annex B (normative) Lines on construction technical drawings ............................................................ 36

Annex C (informative) Examples of application on construction technical drawings .................... 40

Annex D (normative) Types of lines and their application on mechanical engineering

technical drawings ....................................................................................................................................... 48

Annex E (informative) Examples of application on mechanical engineering technical

drawings .......................................................................................................................................................... 53

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ISO/FDIS 128-2:2022(E)

Annex F (normative) Types of lines and their application on shipbuilding technical

drawings .......................................................................................................................................................... 77

Annex G (informative) Application examples of the different types of lines on shipbuilding

technical drawings ....................................................................................................................................... 80

Bibliography ............................................................................................................................................................... 100

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ISO/FDIS 128-2:2022(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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. Details of any

patent rights identified during the development of the document will be in the Introduction and/or on

the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the World

Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT)), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 10, Technical product documentation., in

collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/SS F01,

Technical drawings, in accordance with the Agreement on technical cooperation between ISO and CEN

(Vienna Agreement).

This second edition cancels and replaces the first edition (ISO 128-2:2020)), of which it constitutes a

minor revision. The changes are as follows:

— the term “line element” is changed to “graphical basic element” in all placesthroughout;

— in Annex C, Table C.1, the right-hand cell in the header has been changed from “Example” to “Figure

no.” to be consistent with Table E.1;

— in Annex D, Table D.1, item 04.2.1 duplicated, duplicate text has been deletedremoved;

— in Annex G, Table G.1, the third header cell from the left, in the header has been changed from

“Example” to “Application” to be consistent with Table C.1 and Table E.1;

— in Annex E, Table E.1 and in Annex G, Table G.1, the right-hand cell in the header has been changed

from “Figure“” to “Example” to be consistent with the rest of the document;
— minor editorial changes.
A list of all parts in the ISO 128 series can be found on the ISO website.
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ISO/FDIS 128-2:2022(E)

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
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ISO/FDIS 128-2:2022(E)
Introduction

ISO 128-2This document contains generally applicable rules for the presentation of lines in all kinds of

technical product documentation.

All figures in this document have been drawn in first-angle projection. It should be understood that third-

angle projection or other methods could have been used equally well without prejudice to the principles

established.

The application of lines within drawings of special technical fields varies considerably. Therefore, rules

of application specific to technical fields are given in Annexes B to G.

Annex A provides information for the calculation of the most important basic types of non-continuous

lines according to types of lines and their graphical basic elements.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 128-2:2022(E)
Technical product documentation — General principles of
representation — Part 2: Basic conventions for lines
1 Scope

This document establishes the types of lines used in technical drawings (e.g. diagrams, plans or maps),

their designations and their configurations, as well as general rules for the draughting of lines. In addition,

this document specifies general rules for the representation of leader and reference lines and their

components as well as for the arrangement of instructions on or at leader lines in technical documents.

Annexes have been provided for specific information on mechanical, construction and shipbuilding

technical drawings.

For the purposes of this document the term “technical drawing” is interpreted in the broadest possible

sense, encompassing the total package of documentation specifying the product (workpiece,

subassembly, assembly).
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 128-3, Technical drawings — General principles of representation — Part 3: Views, sections and cuts

ISO 128-15, Technical product documentation (TPD) — General principles of presentation — Part 15:

Presentation of shipbuilding drawings

ISO 129-1, Technical product documentation (TPD) — Presentation of dimensions and tolerances — Part

1: General principles

ISO 129-5, Technical product documentation (TPD) — Presentation— Indication of dimensions and

tolerances — Part 5: Dimensioning of structural metal work

ISO 1101, Geometrical product specifications (GPS) — Geometrical tolerancing — Tolerances of form,

orientation, location and run-out
ISO 2203, Technical drawings — Conventional representation of gears

ISO 2538-2, Geometrical product specifications (GPS) — Wedges — Part 2: Dimensioning and tolerancing

ISO 2553, Welding and allied processes — Symbolic representation on drawings — Welded joints

ISO 3040, Geometrical product specifications (GPS) — Dimensioning and tolerancing — Cones

ISO 3766, Construction drawings — Simplified representation of concrete reinforcement

ISO 4463-1, Measurement methods for building — Setting-out and measurement — Part 1: Planning and

organization, measuring procedures, acceptance criteria
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ISO/FDIS 128-2:2022(E)

ISO 4463-3, Measurement methods for building — Setting-out and measurement — Part 3: Check-lists for

the procurement of surveys and measurement services

ISO 5261, Technical drawings — Simplified representation of bars and profile sections

ISO 5455, Technical drawings — Scales
ISO 5456-4, Technical drawings — Projection methods — Part 4: Central projection

ISO 5459, Geometrical product specifications (GPS) — Geometrical tolerancing — Datums and datum

systems

ISO 6410-1, Technical drawings — Screw threads and threaded parts — Part 1: General conventions

ISO 6428, Technical drawings — Requirements for microcopying

ISO 7437, Technical drawings — Technical drawings — Construction drawings — General rules for

execution of production drawings for prefabricated structural components

ISO 7519, Technical drawings — Construction drawings — General principles of presentation for general

arrangement and assembly drawings

ISO 8560, Technical drawings — Construction drawings — Representation of modular sizes, lines and grids

ISO 10110-1, Optics and photonics — Preparation of drawings for optical elements and systems — Part 1:

General

ISO 10135, Geometrical product specifications (GPS) — Drawing indications for moulded parts in technical

product documentation (TPD)

ISO 10209, Technical product documentation — Vocabulary — Terms relating to technical drawings,

product definition and related documentation
ISO 11091, Construction drawings — Landscape drawing practice

ISO 12671, Thermal spraying — Thermally sprayed coatings — Symbolic representation on drawings

ISO 15785, Technical drawings — Symbolic presentation and indication of adhesive, fold and pressed joints

ISO 15787, Technical product documentation — Heat-treated ferrous parts — Presentation and indications

ISO 16792, Technical product documentation — Digital product definition data practices

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 10209 and the following apply.

ISO and IEC maintain terminologicalterminology databases for use in standardization at the following

addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
graphical basic element
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ISO/FDIS 128-2:2022(E)

continuous graphical object with rounded or squared end shape which is represented in any way (e.g.

straight, curved), which has a length and a width
Note 1 to entry: See Figure A.1.
3.2
dot
graphical basic element (3.1) having a length equal to the width, d
Note 1 to entry: See Figure A.2.
3.3
line

set of one or more graphical basic elements (3.1) having a length of more than the width

Note 1 to entry: See Figure A.3.
3.4
technical drawing

drawing showing a technical installation, process or product with a view to clarifying its structure and

enabling its construction
[SOURCE: ISO 5127:2017, 3.4.7.54, modified — Note 1 to entry removed.]
4 Types of lines
4.1 General

The line type designation consists of a combination of a basic line type and a subtype, depending on the

line width, see 4.2.

For the purposes of this document a line type application number is used to number the application

examples for the line types.
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ISO/FDIS 128-2:2022(E)

For applying line types to construction technical drawings, Annex B shall be applied. For applying line

types to mechanical engineering technical drawings, Annex D shall be applied. For applying line types to

ship building technical drawings, Annex F shall be applied.
4.2 Basic types
The basic line types are given in Table 1.
Table 1 — Basic line types
No. Representation Description
01 Continuous line
02 Dashed line
03 Dashed spaced line
04 Long-dashed dotted line
05 Long-dashed double-dotted line
06 Long-dashed triplicate-dotted line
07 Dotted line
08 Long-dashed short-dashed line
Long-dashed double-short-dashed
line
10 Dashed dotted line
11 Double-dashed dotted line
12 Dashed double-dotted line
13 Double-dashed double-dotted line
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ISO/FDIS 128-2:2022(E)
14 Dashed triplicate-dotted line
15 Double-dashed triplicate-dotted line
4.3 Line sub types subtypes
The line sub typessubtypes are given in Table 2.
Table 2 — Line sub typessubtypes
Sub-
typeSubtype Representation Description
no.
.1 Narrow
.2 Wide
.3 Extra-wide
Line identification structure
4.4 Variations of the basic types of lines

The straight lines in Table 1 and the line widths of Table 2 can have variations as shown in Table 3.

Table 3 — Line variations
Representation Description
Uniform wavy continuous line
Uniform spiral continuous line
Uniform zigzag continuous line
Freehand /or freeform curve continuous
line

NOTE Table 3 This table contains only variations of the basic type of line Nono. 01. Variations of the basic types of Nosno. 02 to no. 15

are possible and are presented in the same way.
4.5 Combinations of lines with the same length
4.5.1 Arrangement of two or more lines parallel to each other
For examples see Figure 1.
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ISO/FDIS 128-2:2022(E)
Figure 1 — Example of lines parallel to each other
4.5.2 Arrangement of two different types of lines
a) With different line widths superimposed. See Figure 2 a) and b) for examples.
b) A continuous line and a dashed spaced
a) A continuous line and a dotted line
line
Figure 2 — Example of superimposed lines
b) Arranged next to each other. See Figure 3 for an example.
Figure 3 — Two continuous narrow lines either side of a wide dashed line

4.5.3 Arrangement of two continuous lines parallel to each other with regularly recurring

connecting elements between them
See Figure 4 a) and b) for examples.
a) Filled circular elements b) Filled trapezoidal elements

Figure 4 — Example of lines parallel to each other with regularly recurring connecting elements

4.5.4 Arrangement of regularly recurring geometric pictorial elements in association with

continuous lines
a) Without interruption of a continuous line. See Figure 5 for examples.
Figure 5 — Without interruption of a continuous line
b) With interruption of a continuous line. See Figure 6 for examples.
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ISO/FDIS 128-2:2022(E)
Figure 6 — With interruption of a continuous line
5 Line dimensions
5.1 Line width

The width, d, of all types of lines shall be one of the following depending on the type and size of the

technical drawing. This series is based on a common ratio 1: √2 (≈1:1,4).
0,13 mm; 0,18 mm; 0,25 mm; 0,35 mm; 0,5 mm; 0,7 mm; 1 mm; 1,4 mm; 2 mm.
The widths of extra-wide, wide and narrow lines are in the ratio 4:2:1.
The line width of any one line shall be constant throughout the whole line.

See Annexes B, D and F for information on line widths pertaining to construction, mechanical and

shipbuilding technical drawings.
5.2 Deviation in line width

Line widths can deviate from those specified in 5.1 providing that it is possible to differentiate

unambiguously between two adjacent lines with different widths. If technical drawing equipment which

produces constant line width is used, the deviation in line width between two such lines shall not be

greater than ± 0,1d.
5.3 Configuration of lines

For the preparation of technical drawings, the lengths of graphical basic elements should conform to

those of Table 4.
Table 4 — Lengths of graphical basic elements
Drawing element Line type no. Length
04 to 07 and
Dot ≤ d
10 to 15
02 and
Gap 3d
04 to 15
Short dash 08 and 09 6d
02, 03 and
Dash 12d
10 to 15
04 to 06,
Long dash ≈24d
08 and 09
Space 03 18d

NOTE The lengths shown in this table are valid for graphical basic elements with semi-

circular and squared ends. In the case of graphical basic elements with semi-circular ends,

the length of the graphical basic element corresponds to the distance covered by a technical

pen (with a tubular tip and using India ink) from the origin up to the end of the graphical

basic element. The total length of such a graphical basic element is the sum of the length

shown in this table, plus d.
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ISO/FDIS 128-2:2022(E)

Formulae for the calculation of some of the basic types of lines and graphical basic elements are given in

Annex A. The formulae are intended to facilitate the preparation of technical drawings using computer-

aided design (CAD) systems.
6 Draughting of lines
6.1 Spacing
The minimum space between parallel lines should not be less than 0,7 mm.

In certain cases when computer-aided technical drawing techniques are used, the spacing of lines on the

technical drawing does not represent the actual spacing, for example for the representation of screw

threads. This has to be considered when data sets are established, for example for the operation of

machine tools.
6.2 Junctions
6.2.1 Types

The basic types of lines, nosno. 02 to no. 06 and nosno. 08 to no. 15, should meet at a dash to avoid

ambiguity; see Figures 7 to 12.
Figure 7 — Long-dashed short-dashed lines intersecting as a cross
Figure 8 — Dashed lines intersecting as a cross
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ISO/FDIS 128-2:2022(E)
Figure 9 — Dashed lines intersecting as a partial cross
Figure 10 — Four dashed lines meeting at an intersection

Figure 11 — Dash dotted lines intersecting as a cross and dashed lines meeting at corners

Figure 12 — Dashed lines meeting at corners and at intersection

Lines of basic type no. 07 should meet at a dot to avoid ambiguity, see Figure 13.

Figure 13 — Dotted lines intersecting at a dot
6.2.2 Representation

Techniques for applying the recommendations of 6.2.1 are to start the lines at the junction (see Figure 14)

or by using a complete, or partial, cross or Y (see Figures 15 and 16).
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ISO/FDIS 128-2:2022(E)
Figure 14 — Partial cross intersection
Figure 15 — Cross intersection
Figure 16 — Y intersection
6.3 Location of a second line

Two different ways of presenting two parallel lines are shown in Figures 17 and 18.

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ISO/FDIS 128-2:2022(E)
Figure 17 — Example of parallel lines with solid line above dashed line
Figure 18 — Example of parallel lines with dashed line above solid line
6.4 Hierarchy of overlapping lines
The rules of overlapping types of lines are defined in Annex D.
7 Colours

Lines shall be drawn in black or white depending on the colour of the background. By default, lines are

black on a white background. Other standardized colours may also be used for technical drawing

standardized lines. In this case, the meaning of the colours shall be explained.
8 Designation

The designation of the basic types of lines shall comprise the following elements in the order given, with

spaces between the elements:
a) “Line”;
b) reference to this document;
c) dash separator;
d) the number of the basic type in accordance with Table 1;
e) the multiplication sign “×”;
f) the line width in accordance with 5.1;
g) forward slash (when the colour is indicated);
h) colour (when indicated).
EXAMPLES
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ISO/FDIS 128-2:2022(E)
Designation of a line of type no. 03 (03), line width 0,25 mm (0,25):
Line ISO 128--2 - 03 × 0,25

Designation of a line of type no. 05 (05), line width 0,13 mm (0,13) and blue in colour:

Line ISO 128--2 - 05 × 0,13/blue
9 Basic conventions and applications for leader lines and reference lines
9.1 Presentation of leader lines

Leader lines are executed as continuous narrow lines (type 01.1) in accordance with this document. They

are drawn at an angle to the relevant representation and/or the frame limiting the drawing sheet, and

not parallel to nearby lines, such as hatching lines. The inclination to the relevant lines shall be > 15°. See

Figures 19 to 31.

Leader lines may be drawn with sharp kinks (see Figure 23), and two or more leader lines may start from

the same point (see Figures 20, 23, 25, 26 and 29). They should not cross other leader lines (see

Figure 23) except when the leader line starts from the same point and is colinear (see

Figure 25, 26 and 29), reference lines or indications, such as graphical symbols or dimensional values.

Leader lines shall terminate at the end which touches the features as follows:

— with a closed and filled arrowhead or a closed arrowhead as per ISO 129-1 if the leader line ends at

lines which represent outlines or edges of parts, piping or cables in plans, charts or diagrams;

arrowheads are also drawn at crossing points of these lines with other lines, for example lines of

symmetry (see the examples given in Figures 19 to 25);

If several parallel lines have to be designated, oblique strokes instead of arrowheads are permitted (see

IEC 61082-1). See the example given in Figure 26.

— with a dot (d = 5 × line width) if the leader line ends on the surface of an object (see the examples

given in Figures 27 to 29);

— without any termination if the leader line ends at another line, for example dimension line or line of

symmetry (see the examples given in Figures 30 and 31).
Figure 19 — Example of a leader line terminating at the edge of a diameter

Figure 20 — Example of leader lines starting at the same point and terminating at part edges

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ISO/FDIS 128-2:2022(E)
Figure 21 — Example of leader lines terminating at outlines
Figure 22 — Example of leader lines not overlapping cross section lines
Figure 23 — Example of a leader line with a sharp kink

Figure 24 — Example of a leader line terminating aat the crossing point of two lines

Figure
...

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 128-2
ISO/TC 10
Technical product documentation
Secretariat: SIS
(TPD) — General principles of
Voting begins on:
2022-05-30 representation —
Voting terminates on:
Part 2:
2022-08-22
Basic conventions for lines
Documentation technique de produits (TPD) — Principes généraux de
représentation —
Partie 2: Conventions de base pour les traits
ISO/CEN PARALLEL PROCESSING
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 SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 128-2:2022(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2022
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ISO/FDIS 128-2:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on

the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below

or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
© ISO 2022 – All rights reserved
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ISO/FDIS 128-2:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 S c op e ................................................................................................................................................................................................................................. 1

2 Nor m at i ve r ef er enc e s ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 2

4 T ypes of lines ............................................................................................................................................................................................................ 3

4 .1 G ener a l ........................................................................................................................................................................................................... 3

4.2 B asic types ................................................................................................................................................................................................. 3

4.3 L ine subtypes ........................................................................................................................................... ................................................ 4

4.4 V ariations of the basic types of lines .................................................................................................................................. 4

4.5 C ombinations of lines with the same length ................................................................................................................ 4

4.5.1 Arrangement of two or more lines parallel to each other ............................................................. 4

4.5.2 A rrangement of two different types of lines ............................................................................................. 5

4.5.3 Arrangement of two continuous lines parallel to each other with regularly

recurring connecting elements between them ....................................................................................... 5

4.5.4 A rrangement of regularly recurring geometric pictorial elements in

association with continuous lines ....................................................................................................................... 5

5 Li ne di mens ions .................................................................................................................................................................................................... 6

5 .1 L i ne w idt h ................................................................................................................................................................................................... 6

5.2 D eviation in line width .................................................................................................................................................................... 6

5.3 C onfiguration of lines ....................................................................................................................................................................... 6

6 D raughting of lines ............................................................................................................................................................................................ 7

6 .1 Sp ac i n g ........................................................................................................................................................................................................... 7

6 . 2 Ju nc t ion s ....................................................................................................................................................................................................... 7

6.2.1 T ypes ............................................................................................................................................................................................. 7

6 . 2 . 2 R epr e s ent at ion ..................................................................................................................................................................... 9

6.3 L ocation of a second line ............................................................................................................................................................. 10

6.4 H ierarchy of overlapping lines............................................................................................................................................... 10

7 C olou r s .........................................................................................................................................................................................................................11

8 D e sig n at ion .............................................................................................................................................................................................................11

9 B asic conventions and applications for leader lines and reference lines ............................................11

9.1 P resentation of leader lines ..................................................................................................................................................... 11

9.2 R epresentation of reference lines ....................................................................................................................................... 14

9.3 I ndication of instructions ..........................................................................................................................................................15

Annex A (informative) Preparation of lines by CAD systems .................................................................................................17

Annex B (normative) Lines on construction technical drawings ......................................................................................30

Annex C (informative) Examples of application on construction technical drawings ................................33

Annex D (normative) Types of lines and their application on mechanical engineering

technical drawings .........................................................................................................................................................................................39

Annex E (informative) Examples of application on mechanical engineering technical

drawings ....................................................................................................................................................................................................................43

Annex F (normative) Types of lines and their application on shipbuilding technical

drawings ....................................................................................................................................................................................................................55

Annex G (informative) Application examples of the different types of lines on shipbuilding

technical drawings .........................................................................................................................................................................................57

Bibliography .............................................................................................................................................................................................................................68

iii
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ISO/FDIS 128-2:2022(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 10, Technical product documentation,

in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/

SS F01, Technical drawings, in accordance with the Agreement on technical cooperation between ISO

and CEN (Vienna Agreement).

This second edition cancels and replaces the first edition (ISO 128-2:2020), of which it constitutes a

minor revision. The changes are as follows:
— the term “line element” changed to “graphical basic element” throughout;

— in Annex C, Table C.1, the right-hand cell in the header has been changed from “Example” to “Figure

no.” to be consistent with Table E.1;
— in Annex D, Table D.1, item 04.2.1, duplicate text removed;

— in Annex G, Table G.1, the third header cell from the left has been changed from “Example” to

“Application” to be consistent with Table C.1 and Table E.1;

— in Annex E, Table E.1 and in Annex G, Table G.1, the right-hand cell in the header has been changed

from “Figure” to “Example” to be consistent with the rest of the document;
— minor editorial changes.
A list of all parts in the ISO 128 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2022 – All rights reserved
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ISO/FDIS 128-2:2022(E)
Introduction

This document contains generally applicable rules for the presentation of lines in all kinds of technical

product documentation.

All figures in this document have been drawn in first-angle projection. It should be understood that

third-angle projection or other methods could have been used equally well without prejudice to the

principles established.

The application of lines within drawings of special technical fields varies considerably. Therefore, rules

of application specific to technical fields are given in Annexes B to G.

Annex A provides information for the calculation of the most important basic types of non-continuous

lines according to types of lines and their graphical basic elements.
© ISO 2022 – All rights reserved
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 128-2:2022(E)
Technical product documentation (TPD) — General
principles of representation —
Part 2:
Basic conventions for lines
1 S cope

This document establishes the types of lines used in technical drawings (e.g. diagrams, plans or

maps), their designations and their configurations, as well as general rules for the draughting of lines.

In addition, this document specifies general rules for the representation of leader and reference lines

and their components as well as for the arrangement of instructions on or at leader lines in technical

documents. Annexes have been provided for specific information on mechanical, construction and

shipbuilding technical drawings.

For the purposes of this document the term “technical drawing” is interpreted in the broadest

possible sense, encompassing the total package of documentation specifying the product (workpiece,

subassembly, assembly).
2 Normat ive references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 128-3, Technical drawings — General principles of representation — Part 3: Views, sections and cuts

ISO 128-15, Technical product documentation (TPD) — General principles of presentation — Part 15:

Presentation of shipbuilding drawings

ISO 129-1, Technical product documentation (TPD) — Presentation of dimensions and tolerances — Part 1:

General principles

ISO 129-5, Technical product documentation — Indication of dimensions and tolerances — Part 5:

Dimensioning of structural metal work

ISO 1101, Geometrical product specifications (GPS) — Geometrical tolerancing — Tolerances of form,

orientation, location and run-out
ISO 2203, Technical drawings — Conventional representation of gears

ISO 2538-2, Geometrical product specifications (GPS) — Wedges — Part 2: Dimensioning and tolerancing

ISO 2553, Welding and allied processes — Symbolic representation on drawings — Welded joints

ISO 3040, Geometrical product specifications (GPS) — Dimensioning and tolerancing — Cones

ISO 3766, Construction drawings — Simplified representation of concrete reinforcement

ISO 4463-1, Measurement methods for building — Setting-out and measurement — Part 1: Planning and

organization, measuring procedures, acceptance criteria

ISO 4463-3, Measurement methods for building — Setting-out and measurement — Part 3: Check-lists for

the procurement of surveys and measurement services
© ISO 2022 – All rights reserved
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ISO/FDIS 128-2:2022(E)

ISO 5261, Technical drawings — Simplified representation of bars and profile sections

ISO 5455, Technical drawings — Scales
ISO 5456-4, Technical drawings — Projection methods — Part 4: Central projection

ISO 5459, Geometrical product specifications (GPS) — Geometrical tolerancing — Datums and datum

systems

ISO 6410-1, Technical drawings — Screw threads and threaded parts — Part 1: General conventions

ISO 6428, Technical drawings — Requirements for microcopying

ISO 7437, Technical drawings — Construction drawings — General rules for execution of production

drawings for prefabricated structural components

ISO 7519, Technical drawings — Construction drawings — General principles of presentation for general

arrangement and assembly drawings

ISO 8560, Technical drawings — Construction drawings — Representation of modular sizes, lines and grids

ISO 10110-1, Optics and photonics — Preparation of drawings for optical elements and systems — Part 1:

General

ISO 10135, Geometrical product specifications (GPS) — Drawing indications for moulded parts in technical

product documentation (TPD)

ISO 10209, Technical product documentation — Vocabulary — Terms relating to technical drawings,

product definition and related documentation
ISO 11091, Construction drawings — Landscape drawing practice

ISO 12671, Thermal spraying — Thermally sprayed coatings — Symbolic representation on drawings

ISO 15785, Technical drawings — Symbolic presentation and indication of adhesive, fold and pressed joints

ISO 15787, Technical product documentation — Heat-treated ferrous parts — Presentation and indications

ISO 16792, Technical product documentation — Digital product definition data practices

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 10209 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
graphical basic element

continuous graphical object with rounded or squared end shape which is represented in any way (e.g.

straight, curved), which has a length and a width
Note 1 to entry: See Figure A.1.
3.2
dot
graphical basic element (3.1) having a length equal to the width, d
Note 1 to entry: See Figure A.2.
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ISO/FDIS 128-2:2022(E)
3.3
line

set of one or more graphical basic elements (3.1) having a length of more than the width

Note 1 to entry: See Figure A.3.
3.4
technical drawing

drawing showing a technical installation, process or product with a view to clarifying its structure and

enabling its construction
[SOURCE: ISO 5127:2017, 3.4.7.54, modified — Note 1 to entry removed.]
4 T ypes of lines
4.1 General

The line type designation consists of a combination of a basic line type and a subtype, depending on the

line width, see 4.2.

For the purposes of this document a line type application number is used to number the application

examples for the line types.

For applying line types to construction technical drawings, Annex B shall be applied. For applying line

types to mechanical engineering technical drawings, Annex D shall be applied. For applying line types

to ship building technical drawings, Annex F shall be applied.
4.2 Basic types
The basic line types are given in Table 1.
Table 1 — Basic line types
No. Representation Description
01 Continuous line
02 Dashed line
03 Dashed spaced line
04 Long-dashed dotted line
05 Long-dashed double-dotted line
06 Long-dashed triplicate-dotted line
07 Dotted line
08 Long-dashed short-dashed line
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ISO/FDIS 128-2:2022(E)
Table 1 (continued)
No. Representation Description
Long-dashed double-short-dashed
line
10 Dashed dotted line
11 Double-dashed dotted line
12 Dashed double-dotted line
13 Double-dashed double-dotted line
14 Dashed triplicate-dotted line
Double-dashed triplicate-dotted
line
4.3 Line subtypes
The line subtypes are given in Table 2.
Table 2 — Line subtypes
Subtype
Representation Description
no.
.1 Narrow
.2 Wide
.3 Extra-wide
Line identification structure
4.4 V ariations of the basic types of lines

The straight lines in Table 1 and the line widths of Table 2 can have variations as shown in Table 3.

Table 3 — Line variations
Representation Description
Uniform wavy continuous line
Uniform spiral continuous line
Uniform zigzag continuous line
Freehand or freeform curve contin-
uous line

NOTE This table contains only variations of the basic type of line no. 01. Variations of the basic types of no. 02 to no. 15 are

possible and are presented in the same way.
4.5 C ombinations of lines with the same length
4.5.1 Arrangement of two or more lines parallel to each other
For examples see Figure 1.
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ISO/FDIS 128-2:2022(E)
Figure 1 — Example of lines parallel to each other
4.5.2 Arrangement of two different types of lines
a) With different line widths superimposed. See Figure 2 a) and b) for examples.

a) A continuous line and a dotted line b) A continuous line and a dashed spaced line

Figure 2 — Example of superimposed lines
b) Arranged next to each other. See Figure 3 for an example.
Figure 3 — Two continuous narrow lines either side of a wide dashed line

4.5.3 Arrangement of two continuous lines parallel to each other with regularly recurring

connecting elements between them
See Figure 4 a) and b) for examples.
a) Filled circular elements b) Filled trapezoidal elements

Figure 4 — Example of lines parallel to each other with regularly recurring connecting

elements

4.5.4 Arrangement of regularly recurring geometric pictorial elements in association with

continuous lines
a) Without interruption of a continuous line. See Figure 5 for examples.
Figure 5 — Without interruption of a continuous line
b) With interruption of a continuous line. See Figure 6 for examples.
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ISO/FDIS 128-2:2022(E)
Figure 6 — With interruption of a continuous line
5 Line dim ensions
5.1 Line width

The width, d, of all types of lines shall be one of the following depending on the type and size of the

technical drawing. This series is based on a common ratio 1: √2 (≈1:1,4).
0,13 mm; 0,18 mm; 0,25 mm; 0,35 mm; 0,5 mm; 0,7 mm; 1 mm; 1,4 mm; 2 mm.
The widths of extra-wide, wide and narrow lines are in the ratio 4:2:1.
The line width of any one line shall be constant throughout the whole line.

See Annexes B, D and F for information on line widths pertaining to construction, mechanical and

shipbuilding technical drawings.
5.2 De viation in line width

Line widths can deviate from those specified in 5.1 providing that it is possible to differentiate

unambiguously between two adjacent lines with different widths. If technical drawing equipment

which produces constant line width is used, the deviation in line width between two such lines shall not

be greater than ± 0,1d.
5.3 Configuration of lines

For the preparation of technical drawings, the lengths of graphical basic elements should conform to

those of Table 4.
Table 4 — Lengths of graphical basic elements
Drawing element Line type no. Length
04 to 07 and
Dot ≤ d
10 to 15
02 and
Gap 3d
04 to 15
Short dash 08 and 09 6d
02, 03 and
Dash 12d
10 to 15
04 to 06,
Long dash ≈24d
08 and 09
Space 03 18d

NOTE The lengths shown in this table are valid for graphical basic elements with semi-

circular and squared ends. In the case of graphical basic elements with semi-circular

ends, the length of the graphical basic element corresponds to the distance covered by a

technical pen (with a tubular tip and using India ink) from the origin up to the end of the

graphical basic element. The total length of such a graphical basic element is the sum of

the length shown in this table, plus d.
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ISO/FDIS 128-2:2022(E)

Formulae for the calculation of some of the basic types of lines and graphical basic elements are given in

Annex A. The formulae are intended to facilitate the preparation of technical drawings using computer-

aided design (CAD) systems.
6 Dr aughting of lines
6.1 Spacing
The minimum space between parallel lines should not be less than 0,7 mm.

In certain cases when computer-aided technical drawing techniques are used, the spacing of lines on

the technical drawing does not represent the actual spacing, for example for the representation of

screw threads. This has to be considered when data sets are established, for example for the operation

of machine tools.
6.2 Junctions
6.2.1 Types

The basic types of lines, no. 02 to no. 06 and no. 08 to no. 15, should meet at a dash to avoid ambiguity;

see Figures 7 to 12.
Figure 7 — Long-dashed short-dashed lines intersecting as a cross
Figure 8 — Dashed lines intersecting as a cross
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ISO/FDIS 128-2:2022(E)
Figure 9 — Dashed lines intersecting as a partial cross
Figure 10 — Four dashed lines meeting at an intersection

Figure 11 — Dash dotted lines intersecting as a cross and dashed lines meeting at corners

Figure 12 — Dashed lines meeting at corners and at intersection

Lines of basic type no. 07 should meet at a dot to avoid ambiguity, see Figure 13.

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ISO/FDIS 128-2:2022(E)
Figure 13 — Dotted lines intersecting at a dot
6.2.2 Representation

Techniques for applying the recommendations of 6.2.1 are to start the lines at the junction (see

Figure 14) or by using a complete, or partial, cross or Y (see Figures 15 and 16).

Figure 14 — Partial cross intersection
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ISO/FDIS 128-2:2022(E)
Figure 15 — Cross intersection
Figure 16 — Y intersection
6.3 Location of a sec ond line

Two different ways of presenting two parallel lines are shown in Figures 17 and 18.

Figure 17 — Example of parallel lines with solid line above dashed line
Figure 18 — Example of parallel lines with dashed line above solid line
6.4 Hier archy of overlapping lines
The rules of overlapping types of lines are defined in Annex D.
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ISO/FDIS 128-2:2022(E)
7 Colours

Lines shall be drawn in black or white depending on the colour of the background. By default, lines

are black on a white background. Other standardized colours may also be used for technical drawing

standardized lines. In this case, the meaning of the colours shall be explained.
8 Designation

The designation of the basic types of lines shall comprise the following elements in the order given,

with spaces between the elements:
a) “Line”;
b) reference to this document;
c) dash separator;
d) the number of the basic type in accordance with Table 1;
e) the multiplication sign “×”;
f) the line width in accordance with 5.1;
g) forward slash (when the colour is indicated);
h) colour (when indicated).
EXAMPLES
Designation of a line of type no. 03 (03), line width 0,25 mm (0,25):
Line ISO 128-2 - 03 × 0,25

Designation of a line of type no. 05 (05), line width 0,13 mm (0,13) and blue in colour:

Line ISO 128-2 - 05 × 0,13/blue
9 Basic c onventions and applications for leader lines and reference lines
9.1 Pr esentation of leader lines

Leader lines are executed as continuous narrow lines (type 01.1) in accordance with this document.

They are drawn at an angle to the relevant representation and/or the frame limiting the drawing

sheet, and not parallel to nearby lines, such as hatching lines. The inclination to the relevant lines shall

be > 15°. See Figures 19 to 31.

Leader lines may be drawn with sharp kinks (see Figure 23), and two or more leader lines may

start from the same point (see Figures 20, 23, 25, 26 and 29). They should not cross other leader

lines (see Figure 23) except when the leader line starts from the same point and is colinear (see

Figure 25, 26 and 29), reference lines or indications, such as graphical symbols or dimensional values.

Leader lines shall terminate at the end which touches the features as follows:

— with a closed and filled arrowhead or a closed arrowhead as per ISO 129-1 if the leader line ends

at lines which represent outlines or edges of parts, piping or cables in p
...

PROJET
NORME ISO/FDIS
FINAL
INTERNATIONALE 128-2
ISO/TC 10
Documentation technique de produits
Secrétariat: SIS
(TPD) — Principes généraux de
Début de vote:
2022-05-30 représentation —
Vote clos le:
Partie 2:
2022-08-22
Conventions de base pour les traits
Technical product documentation (TPD) — General principles of
representation —
Part 2: Basic conventions for lines
TRAITEMENT PARALLÈLE ISO/CEN
LES DESTINATAIRES DU PRÉSENT PROJET SONT
INVITÉS À PRÉSENTER, AVEC LEURS OBSER-
VATIONS, NOTIFICATION DES DROITS DE PRO-
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TATION EXPLICATIVE.
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INDUSTRIELLES, TECHNOLOGIQUES ET COM-
Numéro de référence
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ISO/FDIS 128-2:2022(F)
DES UTILISATEURS, LES PROJETS DE NORMES
INTERNATIONALES DOIVENT PARFOIS ÊTRE
CONSIDÉRÉS DU POINT DE VUE DE LEUR POSSI-
BILITÉ DE DEVENIR DES NORMES POUVANT
SERVIR DE RÉFÉRENCE DANS LA RÉGLEMENTA-
TION NATIONALE. © ISO 2022
---------------------- Page: 1 ----------------------
ISO/FDIS 128-2:2022(F)
PROJET
NORME ISO/FDIS
FINAL
INTERNATIONALE 128-2
ISO/TC 10
Documentation technique de produits
Secrétariat: SIS
(TPD) — Principes généraux de
Début de vote:
2022-05-30 représentation —
Vote clos le:
Partie 2:
2022-08-22
Conventions de base pour les traits
Technical product documentation (TPD) — General principles of
representation —
Part 2: Basic conventions for lines
DOCUMENT PROTÉGÉ PAR COPYRIGHT
© ISO 2022
TRAITEMENT PARALLÈLE ISO/CEN

Tous droits réservés. Sauf prescription différente ou nécessité dans le contexte de sa mise en œuvre, aucune partie de cette

publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique,

LES DESTINATAIRES DU PRÉSENT PROJET SONT

y compris la photocopie, ou la diffusion sur l’internet ou sur un intranet, sans autorisation écrite préalable. Une autorisation peut

INVITÉS À PRÉSENTER, AVEC LEURS OBSER-
VATIONS, NOTIFICATION DES DROITS DE PRO-

être demandée à l’ISO à l’adresse ci-après ou au comité membre de l’ISO dans le pays du demandeur.

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ISO/FDIS 128-2:2022(F)
Sommaire Page

Avant-propos .............................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Domaine d'application ...................................................................................................................................................................................1

2 Références normatives ..................................................................................................................................................................................1

3 Termes et définitions ...................................................................................................................................................................................... 2

4 Types de traits ........................................................................................................................................................................................................ 3

4.1 Généralités ................................................................................................................................................................................................. 3

4.2 Types de base ........................................................................................................................................................................................... 3

4.3 Sous-types de traits ........................................................................................................................................................................... 4

4.4 Variations des types de traits de base ............................................................................................................................... 4

4.5 Combinaisons de traits de même longueur ................................................................................................................... 5

4.5.1 Combinaison de deux traits parallèles entre eux ou plus .............................................................. 5

4.5.2 Combinaison de deux différents types de traits .................................................................................... 5

4.5.3 Combinaison de deux traits continus parallèles avec des éléments de

liaison régulièrement répétés ................................................................................................................................ 5

4.5.4 Combinaison d’éléments picturaux géométriques régulièrement répétés

en association avec des traits continus .......................................................................................................... 6

5 Dimensions des traits .....................................................................................................................................................................................6

5.1 Largeur des traits ................................................................................................................................................................................ 6

5.2 Écart dans la largeur de trait ..................................................................................................................................................... 6

5.3 Configuration des traits ................................................................................................................................................................. 6

6 Tracé de traits......................................................................................................................................................................................................... 7

6.1 Espacement ................................................................................................................................................................................................ 7

6.2 Jonctions ....................................................................................................................................................................................................... 7

6.2.1 Types ............................................................................................................................................................................................. 7

6.2.2 Représentation ..................................................................................................................................................................... 9

6.3 Emplacement d'un deuxième trait ..................................................................................................................................... 10

6.4 Hiérarchie des traits chevauchants .................................................................................................................................. 10

7 Couleurs .....................................................................................................................................................................................................................11

8 Désignation .............................................................................................................................................................................................................11

9 Conventions de base et applications pour les lignes repères et traits de référence ................11

9.1 Présentation des lignes repères ........................................................................................................................................... 11

9.2 Représentation des traits de référence ......................................................................................................................... 14

9.3 Indication des instructions ...................................................................................................................................................... 15

Annexe A (informative) Préparation des traits par systèmes CAO ..................................................................................17

Annexe B (normative) Traits dans des dessins techniques de construction .........................................................30

Annexe C (informative) Exemples d'application sur des dessins techniques de construction ..........33

Annexe D (normative) Types de traits et leur application dans des dessins techniques

industriels ................................................................................................................................................................................................................39

Annexe E (informative) Exemples d'application sur des dessins techniques industriels ........................43

Annexe F (normative) Types de traits et leur application dans des dessins techniques de

construction navale .......................................................................................................................................................................................55

Annexe G (informative) Exemples d’application des différents types de traits dans des

dessins techniques de construction navale .........................................................................................................................58

Bibliographie ...........................................................................................................................................................................................................................70

iii
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ISO/FDIS 128-2:2022(F)
Avant-propos

L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes

nationaux de normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est

en général confiée aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude

a le droit de faire partie du comité technique créé à cet effet. Les organisations internationales,

gouvernementales et non gouvernementales, en liaison avec l'ISO participent également aux travaux.

L'ISO collabore étroitement avec la Commission électrotechnique internationale (IEC) en ce qui

concerne la normalisation électrotechnique.

Les procédures utilisées pour élaborer le présent document et celles destinées à sa mise à jour sont

décrites dans les Directives ISO/IEC, Partie 1. Il convient, en particulier de prendre note des différents

critères d'approbation requis pour les différents types de documents ISO. Le présent document

a été rédigé conformément aux règles de rédaction données dans les Directives ISO/IEC, Partie 2

(voir www.iso.org/directives).

L'attention est attirée sur le fait que certains des éléments du présent document peuvent faire l'objet de

droits de propriété intellectuelle ou de droits analogues. L'ISO ne saurait être tenue pour responsable

de ne pas avoir identifié de tels droits de propriété et averti de leur existence. Les détails concernant

les références aux droits de propriété intellectuelle ou autres droits analogues identifiés lors de

l'élaboration du document sont indiqués dans l'Introduction et/ou dans la liste des déclarations de

brevets reçues par l'ISO (voir www.iso.org/brevets).

Les appellations commerciales éventuellement mentionnées dans le présent document sont données

pour information, par souci de commodité, à l’intention des utilisateurs et ne sauraient constituer un

engagement.

Pour une explication de la nature volontaire des normes, la signification des termes et expressions

spécifiques de l'ISO liés à l'évaluation de la conformité, ou pour toute information au sujet de l'adhésion

de l'ISO aux principes de l’Organisation mondiale du commerce (OMC) concernant les obstacles

techniques au commerce (OTC), voir www.iso.org/avant-propos.

Le présent document a été élaboré par le Comité Technique ISO/TC 10, Documentation technique de

produits, en collaboration avec le Comité Technique CEN/SS F01, Dessins techniques, du Comité Européen

pour la normalisation (CEN), conformément à l'accord sur la coopération technique entre l'ISO et le CEN

(Accord de Vienne).

Cette deuxième édition annule et remplace la première édistion (ISO 128-2:2020), dont elle constitue

une révision mineure. Les changements sont les suivants:

— le terme “élément de traits” a été changé en “élément graphique de base” dans tout le document;

— en Annexe C, Tableau C.1, la cellule de droite dans le titre a été changée d'”Exemple” en “N° de Figure”

pour être cohérente avec le Tableau E.1;
— en Annexe D, Tableau D.1, objet 04.2.1, le texte dupliqué a été retiré;

— en Annexe G, Tableau G.1, la troisième cellule à partir de la gauche dans le titre a été changée

d'”Exemple” en “Application” pour être cohérente avec le Tableau C.1 et le Tableau E.1;

— en Annexe E, Tableau E.1 et en Annexe G, Tableau G.1, la cellule de droite dans le titre a été changée

de “Figure” en “Exemple” pour être cohérente avec le teste du document;
— des changements éditoriaux mineurs.

Une liste de toutes les parties de la série ISO 128 se trouve sur le site web de l’ISO.

Il convient que l’utilisateur adresse tout retour d’information ou toute question concernant le présent

document à l’organisme national de normalisation de son pays. Une liste exhaustive desdits organismes

se trouve à l’adresse www.iso.org/members.html.
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ISO/FDIS 128-2:2022(F)
Introduction

Le présent document comprend des règles généralement applicables pour la représentation de traits

dans toutes sortes de documentations techniques de produits.

Toutes les figures dans le présent document ont été dessinées selon la projection du premier dièdre. Il

convient de comprendre que la projection du troisième dièdre ou tout autres méthodes pourraient aussi

bien être utilisées sans préjudice pour les principes établis.

L’application des traits dans les dessins de domaines techniques spéciaux varie considérablement. Par

conséquent, les règles d’application spécifiques aux champs techniques sont données dans les Annexes B

à G.

L’Annexe A fournit des informations pour le calcul des plus importants types de traits interrompus de

base conformément aux types de traits et à leurs éléments graphiques de base.
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PROJET FINAL DE NORME INTERNATIONALE ISO/FDIS 128-2:2022(F)
Documentation technique de produits (TPD) — Principes
généraux de représentation —
Partie 2:
Conventions de base pour les traits
1 Domaine d'application

Le présent document établit les types de traits utilisés dans les dessins techniques (par exemple

schémas, plans ou cartes), leurs désignations et leurs configurations, ainsi que les règles générales pour

le tracé de traits. De plus, le présent document spécifie des règles générales pour la représentation des

lignes repères et traits de référence et leurs composants, ainsi que pour la disposition des instructions

sur ou aux lignes repères dans les documents techniques. Des annexes ont été prévues pour des

informations spécifiques sur les dessins industriels, dessins de construction et dessins de construction

navale.

Pour les besoins du présent document, le terme «dessin technique» est interprété au sens le plus

large possible, englobant l'ensemble de la documentation spécifiant le produit (pièce, sous-ensemble,

ensemble).
2 Références normatives

Les documents suivants sont cités dans le texte de sorte qu’ils constituent, pour tout ou partie de leur

contenu, des exigences du présent document. Pour les références datées, seule l’édition citée s’applique.

Pour les références non datées, la dernière édition du document de référence s'applique (y compris les

éventuels amendements).

ISO 128-3, Dessins techniques — Principes généraux de représentation — Partie 3: Vues, sections et coupes

ISO 128-15, Documentation technique de produits (TPD) — Principes généraux de représentation —

Partie 15: Représentation des dessins de construction navale

ISO 129-1, Documentation technique de produits — Représentation des dimensions et tolérances —

Partie 1: Principes généraux

ISO 129-5, Technique du produit documentation — Indication des cotes et tolérances — Partie 5: Cotes des

ouvrages de structure métallique

ISO 1101, Spécification géométrique des produits (GPS) — Tolérancement géométrique — Tolérancement

de forme, orientation, position et battement
ISO 2203, Dessins techniques — Représentation conventionnelle des engrenages

ISO 2538-2, Spécification géométrique des produits (GPS) — Coins — Partie 2: Cotation et tolérancement

ISO 2553, Soudage et techniques connexes — Représentations symboliques sur les dessins — Assemblages

soudés

ISO 3040, Spécification géométrique des produits (GPS) — Cotation et tolérancement — Cônes

ISO 3766, Dessins de construction — Représentation simplifiée des armatures de béton

ISO 4463-1, Méthodes de mesurage pour la construction — Piquetage et mesurage — Partie 1: Planification

et organisation, procédures de mesurage et critères d'acceptation
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ISO/FDIS 128-2:2022(F)

ISO 4463-3, Méthodes de mesurage pour la construction — Piquetage et mesurage — Partie 3: Listes de

contrôle pour la fourniture de levés topographiques et de prestations de mesurage

ISO 5261, Dessins techniques — Représentation simplifiée des barres et des profilés

ISO 5455, Dessins techniques — Échelles

ISO 5456-4, Dessins techniques — Méthodes de projection — Partie 4: Projection centrale

ISO 5459, Spécification géométrique des produits (GPS) — Tolérancement géométrique — Références

spécifiées et systèmes de références spécifiées

ISO 6410-1, Dessins techniques — Filetages et pièces filetées — Partie 1: Conventions générales

ISO 6428, Dessins techniques — Conditions requises pour la micrographie

ISO 7437, Dessins techniques — Dessins de construction — Règles générales pour l'élaboration de dessins

d'exécution pour des composants de structure préfabriqués

ISO 7519, Dessins techniques — Dessins de construction — Principes généraux de présentation pour des

dessins d'ensemble et d'assemblage

ISO 8560, Dessins techniques — Dessins de construction — Représentation des dimensions, lignes et

quadrillages modulaires

ISO 10110-1, Optique et photonique — Indications sur les dessins pour éléments et systèmes optiques —

Partie 1: Généralités

ISO 10135, Spécification géométrique des produits (GPS) — Indications sur les dessins pour pièces moulées

dans la documentation technique de produits (TPD)

ISO 10209, Documentation technique de produits — Vocabulaire — Termes relatifs aux dessins techniques,

à la définition de produits et à la documentation associée
ISO 11091, Dessins de construction — Pratique en matière de dessins de paysages

ISO 12671, Projection thermique — Revêtements appliqués par projection thermique — Représentation

symbolique sur les dessins

ISO 15785, Dessins techniques — Représentation symbolique et indication des assemblages collés, repliés

et clinchés

ISO 15787, Documentation technique de produits — Produits ferreux traités thermiquement — Présentation

et indications

ISO 16792, Documentation technique de produits — Pratiques pour les données numériques de la définition

d’un produit
3 Termes et définitions

Pour les besoins du présent document, les termes et définitions donnés dans l’ISO 10209, ainsi que les

suivants s'appliquent.

L'ISO et l'IEC tiennent à jour des bases de données terminologiques destinées à être utilisées en

normalisation, consultables aux adresses suivantes:

— ISO Online browsing platform: disponible à l'adresse https:// www .iso .org/ obp

— Electropedia IEC: disponible à l’adresse https:// www .electropedia .org/
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ISO/FDIS 128-2:2022(F)
3.1
élément graphique de base

objet graphique continu avec une forme d’extrémité arrondie ou carrée qui est représenté d'une

certaine manière (par exemple, droit, arrondi), qui a une longueur et une largeur

Note 1 à l'article: voir la Figure A.1
3.2
point
élément graphique de base (3.1) ayant une longueur égale à la largeur, d
Note 1 à l'article: voir la Figure A.2
3.3
trait

ensemble d'un ou de plusieurs éléments graphiques de base (3.1) ayant une longueur supérieure à la

largeur
Note 1 à l'article: voir la Figure A.3
3.4
dessin technique

dessin montrant une installation technique, un procédé ou un produit dans le but de clarifier sa

structure et permetant sa construction
[SOURCE: ISO 5127:2017, 3.4.7.54, modifié — Note 1 à l'article supprimé.]
4 Types de traits
4.1 Généralités

La désignation d’un type de trait comprend une combinaison d'un type de trait de base et d'un sous-

type, en fonction de la largeur du trait, voir 4.2.

Pour les besoins du présent document un nombre d'application du type de trait est utilisé pour

numéroter les exemples d'application pour les types de trait.

Pour appliquer les types de trait aux dessins techniques de construction, l'Annexe B doit être utilisée.

Pour appliquer les types de trait aux dessins techniques industriels, l'Annexe D doit être utilisée. Pour

appliquer les types de trait aux dessins techniques de construction navale, l'Annexe F doit être utilisée.

4.2 Types de base
Les types de traits de base sont donnés dans le Tableau 1.
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ISO/FDIS 128-2:2022(F)
Tableau 1 — Types de trait de base
N° Representation Description
01 Trait continu
02 Trait interrompu
03 Trait interrompu espacé
Trait mixte à un point et un tiret
long
Trait mixte à deux points et un tiret
long
Trait mixte à trois points et un tiret
long
07 Trait pointillé
08 Trait à un tiret long et un tiret court
Trait à un tiret long et deux tirets
courts
10 Trait mixte à un point et un tiret
11 Trait mixte à un point et deux tirets
12 Trait mixte à deux points et un tiret
Trait mixte à deux points et deux
tirets
14 Trait mixte à trois points et un tiret
Trait mixte à trois points et deux
tirets
4.3 Sous-types de traits
Les sous-types de traits sont donnés dans le Tableau 2.
Tableau 2 — Sous-types de trait
Sous-type
Représentation Description
.1 Fin
.2 Fort
.3 Extra-fort
Structure d'identification du trait
4.4 Variations des types de traits de base

Les traits droits dans le Tableau 1 et les largeurs de trait du Tableau 2 peuvent avoir des variations

telles que montrées dans le Tableau 3.
Tableau 3 — Variations de trait
Représentation Description
Trait continu uniformément ondulé
Trait continu uniformément spiralé

NOTE Ce Tableau comprend seulement des variations du type de trait de base n° 01. Des variations des types de traits de

base des n° 02 à 15 sont également possibles, et sont présentées de la même façon.

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ISO/FDIS 128-2:2022(F)
Tableau 3 (suite)
Représentation Description
Trait continu uniformément zigza-
gué
Trait continu à main levée ou de
forme libre

NOTE Ce Tableau comprend seulement des variations du type de trait de base n° 01. Des variations des types de traits de

base des n° 02 à 15 sont également possibles, et sont présentées de la même façon.

4.5 Combinaisons de traits de même longueur
4.5.1 Combinaison de deux traits parallèles entre eux ou plus
Pour des exemples, voir la Figure 1.
Figure 1 — Exemple de traits parallèles entre eux
4.5.2 Combinaison de deux différents types de traits

a) Avec des traits de largeur différente se chevauchant. Voir la Figure 2 a) et b) pour des exemples.

a) Un trait continu et un trait pointillé b) Un trait continu et un trait interrompu

espacé
Figure 2 — Exemple de traits se chevauchant
b) Traits combinés proches. Voir la Figure 3 pour un exemple.

Figure 3 — Deux traits continus fins tangents de part et d’autre d’un trait épais interrompu

4.5.3 Combinaison de deux traits continus parallèles avec des éléments de liaison

régulièrement répétés
Voir la Figure 4 a) et b) pour des exemples.
a) Éléments circulaires pleins b) Éléments trapézoïdaux pleins

Figure 4 — Exemple de traits parallèles avec des éléments de liaison régulièrement répétés

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ISO/FDIS 128-2:2022(F)

4.5.4 Combinaison d’éléments picturaux géométriques régulièrement répétés en association

avec des traits continus
a) Sans interruption du trait continu. Voir la Figure 5 pour des exemples.
Figure 5 — Sans interruption de trait continu
b) Avec interruption du trait continu. Voir la Figure 6 pour des exemples.
Figure 6 — Avec interruption de trait continu
5 Dimensions des traits
5.1 Largeur des traits

La largeur, d, de tous les types de traits doit être l'une des suivantes en fonction du type et de la taille du

dessin technique. Cette gamme est basée sur un rapport commun 1: √2 (≈ 1:1,4).
0,13 mm; 0,18 mm; 0,25 mm; 0,35 mm; 0,5 mm; 0,7 mm; 1 mm; 1,4 mm; 2 mm
Les largeurs des traits extra-forts, forts et fins sont dans le rapport 4:2:1.
La largeur de tout trait doit être constante tout au long de son tracé.

Voir les Annexes B, D et F pour des informations sur les largeurs de trait se rapportant aux dessins de

construction, dessins industriels et dessins de construction navale.
5.2 Écart dans la largeur de trait

Les largeurs de trait peuvent faire l'objet d'une dérogation par rapport à celles spécifiées en 5.1 pourvu

qu'il soit possible de différencier sans ambiguïté deux traits adjacents avec des largeurs différentes. Si

on utilise des instruments de dessin technique permettant d'obtenir une largeur de trait constante, les

dérogations de largeur de trait entre deux traits ne doivent pas excéder ±0,1d.
5.3 Configuration des traits

Pour la préparation des dessins techniques, il convient que les longueurs d'éléments graphiques de base

soient conformes avec celles du Tableau 4.
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ISO/FDIS 128-2:2022(F)
Tableau 4 — Longueurs des éléments graphiques de base
Élément de dessin Type de trait n° Longueur
04 à 07 et
Point ≤ d
10 à 15
02 et
Espace 3d
04 à 15
Tiret court 08 et 09 6d
02, 03 et
Tiret 12d
10 à 15
04 à 06,
Tiret long ≈24d
08 et 09
Espace 03 18d

NOTE Les longueurs indiquées dans le présent tableau sont valables pour les éléments graphiques

de base dont les extrémités sont semi-circulaires ou à angles droits. Dans le cas d'éléments

graphiques de base à extrémités semi-circulaires, la longueur des éléments graphiques de base

correspond à la distance parcourue par un stylo technique (tubulaire et à encre de Chine), de

l'origine à la fin de l'élément graphique de base. La longueur totale de cet élément graphique de

base est la somme de la longueur donnée dans le présent tableau, plus d.

Des formules pour le calcul de certains des types de traits de base et d'éléments graphiques de base sont

données dans l'Annexe A. Les formules ont pour but de faciliter la préparation de dessins techniques

par les systèmes de conception assistée par ordinateur (CAO).
6 Tracé de traits
6.1 Espacement

Il convient que l'espacement minimal des traits parallèles ne soit pas inférieur à 0,7 mm.

Dans certains cas où des techniques de dessin technique assisté par ordinateur sont utilisées,

l'espacement des traits sur le dessin technique ne représente pas l’espacement réel, par exemple pour la

représentation des filetages. C’est à considérer lors de l'établissement de séries de données, par exemple

pour le fonctionnement des machines-outils.
6.2 Jonctions
6.2.1 Types

Il convient que les types de traits de base, n° 02 à n° 06 et n° 08 à n° 15 se croisent sur un tiret pour

éviter toute ambiguité; voir les Figures 7 à 12.
Figure 7 — Traits à un tiret long et un tiret court se croisant comme une croix
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ISO/FDIS 128-2:2022(F)
Figure 8 — Traits à un tiret se croisant comme une croix
Figure 9 — Traits à un tiret se croisant comme une croix partielle
Figure 10 — Traits à quatre tirets se rencontrant à une intersection

Figure 11 — Traits mixtes à un point et un tiret se croisant comme une croix et traits à un tiret

se rencontrant à des coins
Figure 12 — Traits à un tiret se rencontrant à des coins et à une intersection
© ISO 2022 – Tous droi
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