Geometrical product specifications (GPS) - Dimensional and geometrical tolerances for moulded parts - Part 3: General dimensional and geometrical tolerances and machining allowances for castings using ± tolerances for indicated dimensions (ISO/FDIS 8062-3:2022)

This document specifies the general conditions for the thermomechanical analysis of thermoplastics and thermosetting materials, filled or unfilled, in the form of sheet or moulded parts.
Thermomechanical analysis consists of the determination of deformations of a test specimen under constant load as a function of temperature and/or time.

Geometrische Produktspezifikationen (GPS) - Maß-, Form- und Lagetoleranzen für Formteile - Teil 3: Allgemeine Maß-, Form- und Lagetoleranzen und Bearbeitungszugaben für Gussstücke (ISO/FDIS 8062-3:2022)

Dieses Dokument legt allgemeine Maß-, Form- und Lagetoleranzen sowie Grade für Bearbeitungszugaben für Gussstücke im Lieferzustand mit ± Toleranzen für die angegebenen Maße fest, die dem Käufer in Übereinstimmung mit ISO/TS 8062 2 geliefert werden. Es ist anwendbar für Maß-, Form- und Lagetoleranzen von nach verschiedenen Gießverfahren hergestellten Gussstücken aus allen metallischen Gusswerkstoffen und deren Legierungen.
Dieses Dokument gilt nicht für 3D CAD Modelle ohne Angabe von Maßen.
Dieses Dokument gilt sowohl für (im oder nahe am Zeichnungsschriftfeld der Zeichnung) angegebene allgemeine Maß-, Form- und Lagetoleranzen als auch für (direkt in der Zeichnung angegebene) individuelle Toleranzen und wo besonders in der Zeichnung auf Hinweise von Abschnitt 11 Bezug genommen wird, falls nichts anderes festgelegt ist.
Die in diesem Dokument enthaltenen Maßtoleranzen sind Toleranzen für Längenmaße.
Die in diesem Dokument enthaltenen Form- und Lagetoleranzen sind Toleranzen für:
—   Geradheit;
—   Ebenheit;
—   Rundheit;
—   Parallelität;
—   Rechtwinkligkeit;
—   Symmetrie;
—   Koaxialität.
Dieses Dokument behandelt keine anderen Lagetoleranzen, Winkelmaßtoleranzen oder Zylindrizitätstoleranzen.
Dieses Dokument kann für die Auswahl von individuellen Toleranzwerten angewendet werden.

Spécification géométrique des produits (GPS) - Tolérances dimensionnelles et géométriques des pièces moulées - Partie 3: Tolérances dimensionnelles et géométriques générales et surépaisseurs d'usinage pour les pièces moulées (ISO/FDIS 8062-3:2022)

Le présent document spécifie les tolérances dimensionnelles et géométriques générales ainsi que les classes de surépaisseur d'usinage pour les pièces moulées utilisant des tolérances ± pour les dimensions indiquées telles que livrées à l'acheteur conformément à l'ISO/TS 8062‑2. Il s'applique au tolérancement des dimensions et de la géométrie des pièces moulées en tous métaux et leurs alliages, produites par différents procédés de fabrication par moulage.
Le présent document ne s'applique pas aux modèles CAO 3D utilisés sans dimension indiquée.
Le présent document s'applique à la fois aux tolérances dimensionnelles et géométriques générales (auxquelles il est fait référence dans ou à proximité du cartouche du dessin), sauf spécification contraire et là où il est fait une mention particulière sur le dessin selon l'une des références de l'Article 11.
Les tolérances dimensionnelles couvertes par le présent document sont les tolérances pour des dimensions linéaires.
Les tolérances géométriques couvertes par le présent document sont des tolérances pour:
—    la rectitude;
—    la planéité;
—    la circularité;
—    le parallélisme;
—    la perpendicularité;
—    la symétrie;
—    la coaxialité.
Le présent document ne couvre pas les autres tolérances de localisation, dimensionnelles angulaires ou de cylindricité.
Le présent document peut être utilisé pour le choix des valeurs de tolérance pour des indications individuelles.

Specifikacija geometrijskih veličin izdelka (GPS) - Dimenzijske in geometrijske tolerance zaformanih delov - 3. del: Splošne dimenzijske in geometrijske tolerance ter dodatki za strojno obdelavo ulitkov z uporabo ± toleranc za navedene dimenzije (ISO/FDIS 8062-3:2022)

General Information

Status
Not Published
Public Enquiry End Date
09-Sep-2019
Technical Committee
Current Stage
5020 - Formal vote (FV) (Adopted Project)
Start Date
12-Oct-2022
Due Date
30-Nov-2022
Completion Date
13-Oct-2022

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SLOVENSKI STANDARD
oSIST prEN ISO 8062-3:2019
01-september-2019
Specifikacija geometrijskih veličin izdelka (GPS) - Dimenzijske in geometrijske

tolerance zaformanih delov - 3. del: Splošne dimenzijske in geometrijske tolerance

ter dodatki za obdelavo ulitkov (ISO/DIS 8062-3:2019)

Geometrical product specifications (GPS) - Dimensional and geometrical tolerances for

moulded parts - Part 3: General dimensional and geometrical tolerances and machining

allowances for castings (ISO/DIS 8062-3:2019)
Geometrische Produktspezifikationen (GPS) - Maß-, Form- und Lagetoleranzen für
Formteile - Teil 3: Allgemeine Maß-, Form- und Lagetoleranzen und
Bearbeitungszugaben für Gussstücke (ISO/DIS 8062-3:2019)
Spécification géométrique des produits (GPS) - Tolérances dimensionnelles et
géométriques des pièces moulées - Partie 3: Tolérances dimensionnelles et

géométriques générales et surépaisseurs d'usinage pour les pièces moulées (ISO/DIS

8062-3:2019)
Ta slovenski standard je istoveten z: prEN ISO 8062-3
ICS:
17.040.10 Tolerance in ujemi Limits and fits
17.040.40 Specifikacija geometrijskih Geometrical Product
veličin izdelka (GPS) Specification (GPS)
oSIST prEN ISO 8062-3:2019 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 8062-3:2019
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oSIST prEN ISO 8062-3:2019
DRAFT INTERNATIONAL STANDARD
ISO/DIS 8062-3
ISO/TC 213 Secretariat: BSI
Voting begins on: Voting terminates on:
2019-06-18 2019-09-10
Geometrical product specifications (GPS) — Dimensional
and geometrical tolerances for moulded parts —
Part 3:
General dimensional and geometrical tolerances and
machining allowances for castings

Spécification géométrique des produits (GPS) — Tolérances dimensionnelles et géométriques des pièces

moulées —

Partie 3: Tolérances dimensionnelles et géométriques générales et surépaisseurs d'usinage pour les pièces

moulées
ICS: 17.040.10
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 8062-3:2019(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2019
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oSIST prEN ISO 8062-3:2019
ISO/DIS 8062-3:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019

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
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Published in Switzerland
ii © ISO 2019 – All rights reserved
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oSIST prEN ISO 8062-3:2019
ISO/DIS 8062-3:2019(E)
Contents Page

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

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

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

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

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

4 Symbols .......................................................................................................................................................................................................................... 2

5 Tolerance grades .................................................................................................................................................................................................. 2

5.1 General ........................................................................................................................................................................................................... 2

5.2 Dimensional casting tolerance grades (DCTG) ............................................................................................................ 2

5.3 Geometrical casting tolerance grades (GCTG) ............................................................................................................. 3

5.3.1 General...................................................................................................................................................................................... 3

5.3.2 Nominal dimensions ..................................................................................................................................................... 4

5.3.3 Datums...................................................................................................................................................................................... 4

6 Surface mismatch (SMI) ................................................................................................................................................................................ 6

7 Wall thickness ......................................................................................................................................................................................................... 7

8 Required machining allowances (RMA) ....................................................................................................................................... 7

8.1 General ........................................................................................................................................................................................................... 7

8.2 Required machining allowance grades (RMAG)......................................................................................................... 7

9 Indication on drawings .................................................................................................................................................................................. 8

9.1 Indication of general dimensional casting tolerances .......................................................................................... 8

9.2 Indication of machining allowances ..................................................................................................................................... 9

9.3 Indication of geometrical casting tolerances ................................................................................................................ 9

10 Rejection ....................................................................................................................................................................................................................10

Annex A (informative) Casting tolerances and geometrical tolerances ........................................................................11

Annex B (informative) Required machining allowance grades (RMAG).......................................................................14

Annex C (informative) Concept of general tolerancing of characteristics ..................................................................15

Annex D (informative) Datums for general geometrical tolerances.................................................................................17

Annex E (informative) Application of general geometrical tolerances for castings .........................................21

Annex F (informative) Relation to the GPS matrix model ............................................................................................................29

Bibliography .............................................................................................................................................................................................................................30

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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 213, Dimensional and geometrical product

specifications and verification.

This second edition cancels and replaces the first edition (ISO 8062-3:2007), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— clarification of inconsistencies.
A list of all parts in the ISO 8062- 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.
iv © ISO 2019 – All rights reserved
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Introduction

This document is a geometrical product specification (GPS) standard and is regarded as a

complementary process-specific tolerance standard (see ISO 14638). It influences chain link A, B and C

of the chain of standards on mouldings.

For more detailed information on the relation of this standard to other standards and the GPS matrix

model, see Annex F.

This part of ISO 8062 defines a system of tolerance grades and machining allowance grades for cast

metals and their alloys. Guidance on its application is given in ISO/TS 8062-2.

It is noted that the dimensional specifications introduced by the application of ISO 8062-3 can be

ambiguous, when it is applied to a dimension which is not a size (see ISO 14405-2).

The specified system applies if the manufacturer provides a pattern or die equipment or accepts

responsibility for proving it.

The tolerances specified for a casting may determine the casting method. It is therefore recommended,

before the design or the order is finalized, that the customer liaises with the foundry to discuss:

a) the proposed casting design and accuracy required;
b) machining requirements;
c) method of casting;
d) location of the parting surfaces and the necessary draft angles;
e) the number of castings to be manufactured;
f) the casting equipment involved;
g) the consequences of the wear out of the equipment during its life cycle;
h) datum system according to ISO 5459;
i) casting alloy;

j) any special requirements, for instance, individual dimensional and geometrical tolerances, fillet

radii, tolerances and individual machining allowances;

Because the dimensional and geometrical accuracy of a casting is related to production factors,

tolerance grades which can be achieved for various methods and metals are described in Annex A.

k) dimensional tolerances for long series and mass production, where development, adjustment and

maintenance of casting equipment make it possible to achieve close tolerances;
l) dimensional tolerances for short series and single production;
m) geometrical tolerances.
Information on typical required machining allowance grades is given in Annex B.•
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oSIST prEN ISO 8062-3:2019
DRAFT INTERNATIONAL STANDARD ISO/DIS 8062-3:2019(E)
Geometrical product specifications (GPS) — Dimensional
and geometrical tolerances for moulded parts —
Part 3:
General dimensional and geometrical tolerances and
machining allowances for castings
1 Scope

This part of ISO 8062 specifies general dimensional and geometrical tolerances as well as machining

allowance grades for castings as delivered to the purchaser in accordance with ISO 8062-2. It is

applicable for tolerancing of dimensions and geometry of castings in all cast metals and their alloys

produced by various casting manufacturing processes.

This part of ISO 8062 applies to both general dimensional and general geometrical tolerances (referred

to in or near the title block of the drawing), unless otherwise specified and where specifically referred

to on the drawing by one of the references in clause 9.

The dimensional tolerances covered by this part of ISO 8062 are tolerances for linear dimensions.

The geometrical tolerances covered by this part of ISO 8062 are: Tolerances for straightness, flatness,

roundness, parallelism, perpendicularity, symmetry and coaxiality.

This part of ISO 8062 can be used for the selection of tolerance values for individual indications.

NOTE This part of ISO 8062 does not apply to 3D CAD models used without indicated dimensions.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

document (including any amendments) applies.

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

General principles

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

orientation, location and run-out

ISO 1302, Geometrical Product Specifications (GPS) — Indication of surface texture in technical product

documentation

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

ISO 8015, Geometrical product specifications (GPS) — Fundamentals — Concepts, principles and rules

ISO 8062-1, Geometrical product specifications (GPS) — Dimensional and geometrical tolerances for

moulded parts — Part 1: Vocabulary

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

product documentation (TPD)

ISO 10579, Geometrical product specifications (GPS) — Dimensioning and tolerancing — Non-rigid parts

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3 Terms and definitions

For the purpose of this part of ISO 8062, the terms and definitions given in ISO 8062-1, ISO 1101,

ISO 5459 and ISO 10135 apply.
4 Symbols
For the purposes of this International Standard, the symbols of Table 1 apply.
Table 1 — Symbols
Symbol Interpretation Reference
DCT Dimensional casting tolerance 5.2
DCTG Dimensional casting tolerance grade 5.2
GCT Geometrical casting tolerance 5.3
GCTG Geometrical casting tolerance grade 5.3
RMA Required machining allowance 8
RMAG Required machining allowance grade 8
TP Taper + ISO 10135
TM Taper - ISO 10135
SMI Surface mismatch ISO 10135
5 Tolerance grades
5.1 General

Individual general dimensional and geometrical tolerances shall be indicated according to the relevant

GPS standards on dimensional and geometrical tolerancing.

If using general tolerances, it is necessary to investigate whether for functional reasons smaller

tolerances or for economical reasons larger tolerances are needed (see Annex C). In both cases,

individual tolerances are to be indicated.

For drawings where the tolerances according to this part of ISO 8062 apply in a specified restrained

condition only, ISO 10579 shall be referred to on the drawing.
5.2 Dimensional casting tolerance grades (DCTG)

16 dimensional casting tolerance grades are defined and designated DCTG 1 to DCTG 16 (see Table 2).

NOTE 1 For wall thicknesses, see clause 7.
2 © ISO 2019 – All rights reserved
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Table 2 — Linear dimensional casting tolerances (DCT)
All dimensions in millimetres
Nominal
dimensions
Linear dimensional tolerance
related to
for dimensional casting tolerance grade (DCTG)
the mould-
ed part
up to
and
DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG DCTG
above in-
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
clud-
ing
- 10 0,09 0,13 0,18 0,26 0,36 0,52 0,74 1 1,5 2 2,8 4,2 - - - -
10 16 0,1 0,14 0,2 0,28 0,38 0,54 0,78 1,1 1,6 2,2 3 4,4 - - - -
16 25 0,11 0,15 0,22 0,3 0,42 0,58 0,82 1,2 1,7 2,4 3,2 4,6 6 8 10 12
25 40 0,12 0,17 0,24 0,32 0,46 0,64 0,9 1,3 1,8 2,6 3,6 5 7 9 11 14
40 63 0,13 0,18 0,26 0,36 0,5 0,7 1 1,4 2 2,8 4 5,6 8 10 12 16
63 100 0,14 0,2 0,28 0,4 0,56 0,78 1,1 1,6 2,2 3,2 4,4 6 9 11 14 18
100 160 0,15 0,22 0,3 0,44 0,62 0,88 1,2 1,8 2,5 3,6 5 7 10 12 16 20
160 250 - 0,24 0,34 0,5 0,7 1 1,4 2 2,8 4 5,6 8 11 14 18 22
250 400 - - 0,4 0,56 0,78 1,1 1,6 2,2 3,2 4,4 6,2 9 12 16 20 25
400 630 - - - 0,64 0,9 1,2 1,8 2,6 3,6 5 7 10 14 18 22 28
630 1000 - - - - 1 1,4 2 2,8 4 6 8 11 16 20 25 32
1000 1600 - - - - - 1,6 2,2 3,2 4,6 7 9 13 18 23 29 37
1600 2500 - - - - - - 2,6 3,8 5,4 8 10 15 21 26 33 42
2500 4000 - - - - - - - 4,4 6,2 9 12 17 24 30 38 49
4000 6300 - - - - - - - - 7 10 14 20 28 35 44 56
6300 10000 - - - - - - - - - 11 16 23 32 40 50 64

a) For wall thicknesses in grade DCTG 1 to DCTG 15, one grade coarser applies (see clause 7).

b) Grade DCTG 16 exists only for wall thicknesses of castings generally specified to DCTG 15.

NOTE 2 Annex A gives recommendations for the application of the above tolerance grades.

As the default conditions for dimensions, the casting tolerance shall be symmetrically disposed with

respect to the nominal dimension, i. e. with one half on the positive side and one half on the negative side.

If agreed between manufacturer and purchaser for specific reasons, the casting tolerance may

be asymmetric. In such a case the casting tolerance shall be stated individually, in accordance with

ISO 129-1, following the nominal dimensions of the final moulded part.

NOTE 3 In pressure die casting an asymmetric tolerance disposition is often applied because of special

technical reasons.

NOTE 4 In case of a draft angle the nominal dimension is modified by the draft angle (TP or TM).

5.3 Geometrical casting tolerance grades (GCTG)
5.3.1 General

Seven geometrical casting tolerance grades (GCTG) are defined and designated GCTG 2 to GCTG 8 (see

Tables 3 to 6).

NOTE GCT values are not given for grade GCTG 1. This grade is reserved for finer values which may be

required in the future.
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General tolerances on form (straightness, flatness, roundness) and on orientation (parallelism,

perpendicularity) do not apply to features with draft. These features need individual indicated

tolerances according to the function and to the manufacturer’s advice.

Other geometrical tolerances than those given in tables 3 to 6 (e. g. profile, position, common zone

flatness) are to be indicated individually.

Therefore, it is recommended to acquire the information about the design of the mould regarding the

location of the parting surfaces and the amount of draft applied to the features from the manufacturer

in order to complete the drawing, see Introduction.
5.3.2 Nominal dimensions

The nominal dimension to be used in Tables 3 to 6 shall be the longest nominal dimension of the

considered integral feature of the moulded part, disregarding the nominal dimension of not individually

indicated fillets and chamfers.

NOTE 1 Integral feature (see ISO 17450-1) means the real surface which can be touched physically. The

longest nominal dimension in case of a cylinder is diameter or length, in case of rectangular planar surface it is

the longest side.
NOTE 2 This definition is not applicable for 3D shapes.
5.3.3 Datums
5.3.3.1 Datums for general orientation tolerances

For general orientation tolerances according to ISO 8062-3 a datum system is to be specified on the

drawing and to be identified by the indication “ISO 8062-3 DS” in or near the title block of the drawing

as shown in Figure 1.

Figure 1 — Drawing indication for the datum system for general orientation tolerances

according to ISO 8062-3

NOTE This datum system does not apply to general geometrical tolerances on coaxiality and symmetry, see

5.3.3.2 and 5.3.3.3.
5.3.3.2 Datums for general coaxiality tolerances
For datums of general coaxiality tolerances the following applies:

— if one cylindrical feature (internal or external) extends over the whole length of all other cylindrical

coaxial features this feature axis applies as the (single) datum, see Annex D Figure D.1;

— otherwise a common datum applies, composed of the axes of the two most separated features on the

considered drawing centre line, see Annex D Figure D.2; if more than one possibility exist (e. g. inner

or outer features), the feature with the largest diameter applies, see Annex D Figure D.3.

The general tolerances for coaxiality apply also to the datum features themselves, if a common datum

applies.
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5.3.3.3 Datums for general symmetry tolerances
For datums of general symmetry tolerances the following applies:

— if one feature of size (internal or external), composed of two parallel opposite planes, extends over

the whole length of all other co-symmetrical features this feature median plane applies as the

(single) datum, see Annex D Figure D.4;

— otherwise a common datum applies, composed of the median planes of the two most separated

features on the considered drawing centre line (plane), see Annex D Figure D.5; if more than one

possibility exist, the feature with the largest size applies, see Annex D Figure D.6. One of the two

datum features may be cylindrical, see Annex D Figure D.7.

The general tolerances for symmetry apply also to the datum features themselves, if a common datum

applies.
Table 3 — Casting tolerances for straightness
All dimensions in millimetres
Nominal dimension
Straightness tolerance
of the considered
for geometrical casting tolerance grade (GCTG)
integral feature
up to and
above GCTG 2 GCTG 3 GCTG 4 GCTG 5 GCTG 6 GCTG 7 GCTG 8
including
10 10 0,08 0,12 0,18 0,27 0,4 0,6 0,9
30 30 0,12 0,18 0,27 0,4 0,6 0,9 1,4
100 100 0,18 0,27 0,4 0,6 0,9 1,4 2
300 300 0,27 0,4 0,6 0,9 1,4 2 3
1000 1000 0,4 0,6 0,9 1,4 2 3 4,5
3000 3000 - - - 3 4 6 9
6000 6000 - - - 6 8 12 18
10000 - - - 12 16 24 36
Table 4 — Casting tolerances for flatness
All dimensions in millimetres
Longest nominal
dimension of the Flatness tolerance
considered inte- for geometrical casting tolerance grade (GCTG)
gral feature
up to and
above GCTG 2 GCTG 3 GCTG 4 GCTG 5 GCTG 6 GCTG 7 GCTG 8
including
10 10 0,12 0,18 0,27 0,4 0,6 0,9 1,4
30 30 0,18 0,27 0,4 0,6 0,9 1,4 2
100 100 0,27 0,4 0,6 0,9 1,4 2 3
300 300 0,4 0,6 0,9 1,4 2 3 4,5
1000 1000 0,6 0,9 1,4 2 3 4,5 7
3000 3000 - - - 4 6 9 14
6000 6000 - - - 8 12 18 28
10000 - - - 16 24 36 56
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Table 5 — Casting tolerances for roundness, parallelism, perpendicularity and symmetry

All dimensions in millimetres
Longest nominal
dimension of the Tolerance
considered integral for geometrical casting tolerance grade (GCTG)
feature
Up to and
above GCTG 2 GCTG 3 GCTG 4 GCTG 5 GCTG 6 GCTG 7 GCTG 8
including
10 10 0,18 0,27 0,4 0,6 0,9 1,4 2
30 30 0,27 0,4 0,6 0,9 1,4 2 3
100 100 0,4 0,6 0,9 1,4 2 3 4,5
300 300 0,6 0,9 1,4 2 3 4,5 7
1000 1000 0,9 1,4 2 3 4,5 7 10
3000 3000 - - - 6 9 14 20
6000 6000 - - - 12 18 28 40
10000 - - - 24 36 56 80
Table 6 — Casting tolerances for coaxiality
All dimensions in millimetres
Longest nominal
dimension of the Coaxiality tolerance
considered integral for geometrical casting tolerance grade (GCTG)
feature
up to and
above GCTG 2 GCTG 3 GCTG 4 GCTG 5 GCTG 6 GCTG 7 GCTG 8
including
10 10 0,27 0,4 0,6 0,9 1,4 2 3
30 30 0,4 0,6 0,9 1,4 2 3 4,5
100 100 0,6 0,9 1,4 2 3 4,5 7
300 300 0,9 1,4 2 3 4,5 7 10
1000 1000 1,4 2 3 4,5 7 10 15
3000 3000 - - - 9 14 20 30
6000 6000 - - - 18 28 40 60
10000 - - - 36 56 80 120

Other geometrical tolerances are to be indicated by individually indicated geometrical tolerances.

6 Surface mismatch (SMI)

As default condition, the surface mismatch A is controlled indirectly by the control of the linear

dimensions according to Table 2, see Figure 2, therefore the surface mismatch may vary between zero

and the value given in Table 2 depending on the actual local sizes of the feature.

On features without draft, surface mismatch is also controlled and therefore included in form tolerances

for straightness, flatness and roundness given in Tables 3 to 5.

NOTE This is an overruling of the principle of independency. This is because it is often not known whether a

parting line exists and, if so, whether the particular feature is affected.
6 © ISO 2019 – All rights reserved
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oSIST prEN ISO 8062-3:2019
ISO/DIS 8062-3:2019(E)
Key
A Surface mismatch
B Minimum dimension
C Maximum dimension
Figure 2 — Limitation of surface mismatch by linear dimension

If it is necessary to restrict further the value of the surface mismatch, the maximum permissible surface

mismatch, SMI, shall be stated individually according to ISO 10135.
7 Wall thickness

As the default condition, the tolerance for wall thickness in grades DCTG 1 to DCTG 15 shall be one grade

coarser than the general tolerance for other dimensions; for example, if there is a general tolerance on a

drawing of DCTG 10, the tolerance on wall thicknesses shall be DCTG 11.
8 Required machining allowances (RMA)
8.1 General

As a general condition, the specified required machining allowance grades, RMAG, according to this

part of ISO 8062 (see clause 9) applies for the entire final moulded part, i. e. only one value is specified

for all surfaces to be machined, and this value shall be selected from the appropriate dimension range

according to the largest overall dimension (see Table 7).

In sand casting, top surfaces may need more machining allowance than other surfaces. For these

surfaces coarser RMA grades can be selected. Individual machining allowances shall be indicated

according to ISO 1302.
8.2 Required machining allowance grades (RMAG)

10 grades of required machining allowance grades are defined and designated RMAG A to RMAG K (see

Table 7).

NOTE Grades recommended for particular alloys and manufacturing methods are shown in Table B.1 for

information only.
© ISO 2019 – All rights reserved 7
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oSIST prEN ISO 8062-3:2019
ISO/DIS 8062-3:2019(E)
Table 7 — Required machining allowance
All dimensions in millimetres
Largest overall Machinin
...

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