ISO 13988:2021

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 13988
ISO/TC 22/SC 33
Passenger car and light truck vehicle
Secretariat: DIN
wheels — Clip and adhesive balance
Voting begins on:
2021­05­24 weight and rim flange nomenclature,
test procedures and performance
Voting terminates on:
2021­07­19
requirements
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 13988:2021(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 2021

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ISO/FDIS 13988:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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ii © ISO 2021 – All rights reserved

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ISO/FDIS 13988:2021(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Rim flange types . 6
5 Test procedure for clip on balance weight . 6
5.1 Preparation of clip on balance weight for test . 6
5.1.1 Selection of balance weights . 6
5.1.2 Measurement of key dimensions of balance weights . 6
5.1.3 Marking of balance weights . 6
5.2 Preparation of the wheel for clip on balance weight testing . 7
5.2.1 Cleaning . 7
5.2.2 Marking . 7
5.2.3 Measurement of rim flange dimensions . 7
5.3 Installation of clip on balance weight. 7
5.4 Tangential test for clip on balance weight . 8
5.4.1 General. 8
5.4.2 Test equipment . 8
5.4.3 Test sequence . . . 8
5.4.4 Performance requirements tangential force. 9
5.5 Axial removal test for clip on balance weight . 9
5.5.1 Test equipment . 9
5.5.2 Test sequence . . . 9
5.5.3 Performance requirement axial force .10
6 Test procedure for adhesive balance weights for all size weights and wheels .11
6.1 Test equipment .11
6.2 Wheel preparation .12
6.3 Balance weight selection and installation .12
7 Shear adhesion test.13
7.1 Test procedure .13
7.2 Performance .13
8 Pull-off adhesion test .13
8.1 Test procedure .13
8.2 Performance .14
© ISO 2021 – All rights reserved iii

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ISO/FDIS 13988:2021(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 non­governmental, 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 22, Road vehicles, Subcommittee SC 33,
Vehicle dynamics and chassis components.
This second edition cancels and replaces the first edition (ISO 13988:2008), which has been technically
revised. The main changes compared with the previous edition are as follows:
— adhesive balance weights have been added, which covers clip on weights only;
— nomenclature for the balance weight and test procedures and performance requirements for the
adhesive weights have been included.
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 13988:2021(E)

Introduction
This document addresses clip and adhesive balance weights used on passenger car wheels. It provides
general features and configurations of the clip balance weights, general features of the adhesive balance
weights, and general features and configurations for rim dimensions relevant to clip on weights and
defines terms used to describe these features.
This document provides test procedures to evaluate weight retention on the wheel.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 13988:2021(E)
Passenger car and light truck vehicle wheels — Clip and
adhesive balance weight and rim flange nomenclature, test
procedures and performance requirements
1 Scope
This document specifies procedures and minimum performance requirements for testing without
tyres the retention of balance weights for use on wheels for passenger vehicles. It also specifies general
features for configurations of clip balance weights, rim flanges for light alloy and steel wheels intended
for use on passenger cars and adhesive balance weights. Alternative materials and geometries can be
considered in the future.
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 3911, Wheels and rims for pneumatic tyres — Vocabulary, designation and marking
ISO 4000­1, Passenger car tyres and rims — Part 1: Tyres (metric series)
ISO 4000­2, Passenger car tyres and rims — Part 2: Rims
ISO 4223­1, Definitions of some terms used in the tyre industry — Part 1: Pneumatic tyres
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 3911, ISO 4000-1, ISO 4000-2,
ISO 4223-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
clip balance weight assembly
assembly of the weight (3.1.1) and the clip (3.1.3), which is intended for mounting on the rim flange (3.3)
to balance the tyre/wheel assembly about its axis of rotation and thus minimize vibrations due to the
rotation of the tyre/wheel assembly
Note 1 to entry: Figure 1 gives the terminology and nomenclature of balance weight assembly.
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ISO/FDIS 13988:2021(E)

Key
1 clip 7 outer surface of clip 13 weight gap
2 spur 8 balance weight 14 clip insertion point
3 clip depth 9 contact radius 15 back leg of clip
4 spur location 10 front surface 16 clip gap
5 spur depth 11 bottom surface 17 weight depth
6 clip height 12 top surface 18 compound radius
19 compound radius
Figure 1 — Clip balance weight assembly terminology
3.1.1
weight
material of a specified mass with contours to conform to the surface of the rim flange (3.3)
Note 1 to entry: The material is recommended to be free of lead.
3.1.2
clip
specially formed metal affixed to the weight (3.1.1) to mount the balance weight on the rim flange (3.3)
3.1.3
spur
optional part of a clip (3.1.3) that protrudes from its surface interfacing with the rim flange (3.3)
3.1.4
balance weight coating
non­corrosive material coating to avoid corrosion
EXAMPLE Polyester, nylon.
3.1.5
balance weight key dimensions
dimensions that are essential for fitting the balance weight (3.1.1) on the rim flange (3.3)
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ISO/FDIS 13988:2021(E)

3.1.6
balance weight size
size determined by the magnitude of the balance weight (3.1.1) mass
Note 1 to entry: Balance weight size is expressed in grams.
3.1.7
balance weight retention force
static force required to remove the balance weight (3.1.1) from the rim flange (3.3)
Note 1 to entry: Balance weight retention force is expressed in newtons.
3.1.8
balance weight retention
ability of the balance weight (3.1.1) to maintain its secure position on the rim flange (3.3) in various
service conditions
3.1.9
interference
measure of balance weight (3.1.1) press fit computed as the difference between the flange thickness and
the weight gap
3.2
adhesive balance weight assembly
assembly of the weight portion (3.2.1) and the adhesive portion, which is intended for mounting on the
rim to balance the tyre/wheel as
...