EN ISO 20238:2019

Conveyor belts - Drum friction testing (ISO 20238:2018)

ISO 20238:2018 specifies a method of testing to determine the propensity of a conveyor belt to generate heat flame or glow when held stationary, under a given tension, in surface contact around a rotating driven steel drum.
ISO 20238:2018 describes means of varying the conveyor belt tension.
NOTE       For conveyor belts containing steel reinforcement, it may not be possible to conduct this test in full due to the inability of the conveyor belt to comply with the requirements of 7.2. In this case, premature termination according to 7.3 can be necessary.

Fördergurte - Prüfung der Trommelreibung (ISO 20238:2018)

Diese Internationale Norm legt ein Prüfverfahren fest, mit denen die Tendenz eines Fördergurts zum Entflammen oder zum Glühen beurteilt werden kann, wenn er bei einer vorgegebenen Spannung in Kontakt mit einer umlaufenden Stahltrommel gehalten wird.
Methoden zur Veränderung der Spannung des Fördergurts werden beschrieben.
ANMERKUNG   Für Fördergurte mit Stahl-Verstärkung lässt sich diese Prüfung möglicherweise nicht in vollem Umfang durchführen, weil die Anforderungen von 6.2. nicht erfüllt werden. In diesem Fall kann eine vorzeitige Beendigung nach 6.3 erforderlich sein.

Courroies transporteuses - Essais de frottement au tambour (ISO 20238:2018)

ISO 20238:2018 spécifie une méthode d'essai permettant de déterminer la propension d'une courroie transporteuse à générer de la chaleur, une flamme ou une incandescence lorsqu'elle est maintenue immobile, sous une tension donnée, au contact de la surface d'un tambour en acier entraîné en rotation.
ISO 20238:2018 décrit les moyens pour faire varier la tension de la courroie transporteuse.
NOTE       Pour les courroies transporteuses pourvues d'une armature en acier, il peut s'avérer impossible d'effectuer cet essai dans son intégralité en raison de l'incapacité de la courroie transporteuse à satisfaire aux exigences du 7.2. Dans ce cas, un arrêt prématuré selon le 7.3 peut être nécessaire.

Naprave za kontinuirni transport - Trakovi tračnih transporterjev - Preskušanje trenja na pogonskem bobnu (ISO 20238:2018)

Ta evropski standard opisuje preskusno metodo, s katero se ugotavlja nagnjenost traka tračnega transporterja k nastanku toplote, plamena ali žarenja, kadar se drži pri miru pod določeno napetostjo pri površinskem stiku okrog vrtečega se gnanega jeklenega bobna.
Opisani so načini spreminjanja napetosti traku.
OPOMBA: Pri nekaterih vrstah trakov zaradi njihove zgradbe morda ne bo mogoče izvesti tega preskusa, ker trak ni v skladu z zahtevami iz točke 6.2.3.

General Information

• Status: Published
• Publication Date: 26-Feb-2019
• Withdrawal Date: 30-Aug-2019
• ICS: 53.040.20 - Components for conveyors
• Technical Committee: CEN/TC 188 - Conveyor belts
• Drafting Committee: CEN/TC 188/WG 3 - Safety requirements for conveyor belting
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 27-Feb-2019
• Completion Date: 27-Feb-2019
• Directive: 2006/42/EC - Directive 2006/42/EC of the European Parliament and of the Council of 17 May 2006 on machinery, and amending Directive 95/16/EC (recast)
• Mandate: M/396 - Mandate to CEN and Cenelec for standardisation in the field of machinery
• Ref Project: SIST EN ISO 20238:2019 - Conveyor belts - Drum friction testing (ISO 20238:2018)

Relations

• Replaces: EN 1554:2012 - Conveyor belts - Drum friction testing
• Effective Date: 06-Mar-2019

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 20238:2019
01-julij-2019
Nadomešča:
SIST EN 1554:2012
Naprave za kontinuirni transport - Trakovi tračnih transporterjev - Preskušanje
trenja na pogonskem bobnu (ISO 20238:2018)
Conveyor belts - Drum friction testing (ISO 20238:2018)
Fördergurte - Prüfung der Trommelreibung (ISO 20238:2018)
Courroies transporteuses - Essais de frottement au tambour (ISO 20238:2018)
Ta slovenski standard je istoveten z: EN ISO 20238:2019
ICS:
53.040.20 Deli za transporterje Components for conveyors
SIST EN ISO 20238:2019 en,fr,de

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

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SIST EN ISO 20238:2019
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SIST EN ISO 20238:2019
EN ISO 20238
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2019
EUROPÄISCHE NORM
ICS 53.040.20 Supersedes EN 1554:2012
English Version
Conveyor belts - Drum friction testing (ISO 20238:2018)

Courroies transporteuses - Essais de frottement au Fördergurte - Prüfung der Trommelreibung (ISO

tambour (ISO 20238:2018) 20238:2018)
This European Standard was approved by CEN on 21 February 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by

translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 20238:2019 E

worldwide for CEN national Members.
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SIST EN ISO 20238:2019
EN ISO 20238:2019 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 20238:2019
EN ISO 20238:2019 (E)
European foreword

This document (EN ISO 20238:2019) has been prepared by Technical Committee ISO/TC 41 "Pulleys

and belts (including veebelts)" in collaboration with Technical Committee CEN/TC 188 “Conveyor belts”

the secretariat of which is held by SNV.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by August 2019, and conflicting national standards shall

be withdrawn at the latest by August 2019.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN 1554:2012.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,

France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,

Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
Endorsement notice

The text of ISO 20238:2018 has been approved by CEN as EN ISO 20238:2019 without any modification.

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SIST EN ISO 20238:2019
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SIST EN ISO 20238:2019
INTERNATIONAL ISO
STANDARD 20238
First edition
2018-01
Conveyor belts — Drum friction testing
Courroies transporteuses — Essais de frottement au tambour
Reference number
ISO 20238:2018(E)
ISO 2018
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SIST EN ISO 20238:2019
ISO 20238:2018(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2018

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, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved
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SIST EN ISO 20238:2019
ISO 20238:2018(E)
Contents Page

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

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

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

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

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 1

5 Apparatus ..................................................................................................................................................................................................................... 2

6 Test piece ...................................................................................................................................................................................................................... 6

7 Procedure..................................................................................................................................................................................................................... 6

7.1 General ........................................................................................................................................................................................................... 6

7.2 Procedure and test ............................................................................................................................................................................... 6

7.2.1 Selection of test method ............................................................................................................................................ 6

7.2.2 Method A — Tests in still air.................................................................................................................................. 6

7.2.3 Method B — Tests in moving air ........................................................................................................................ 8

7.3 Premature termination .................................................................................................................................................................... 9

8 Test report ................................................................................................................................................................................................................... 9

© ISO 2018 – All rights reserved iii
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SIST EN ISO 20238:2019
ISO 20238:2018(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 on 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 the following

URL: www .iso .org/ iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 41, Pulleys and belts (including veebelts),

Subcommittee SC 3, Conveyor belts.
iv © ISO 2018 – All rights reserved
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SIST EN ISO 20238:2019
ISO 20238:2018(E)
Introduction

The purpose of this document is to provide a method of testing that will assist conveyor belt users in

assessing the degree of risk which can be anticipated from the hazard caused when a conveyor belt

stalls and the drive mechanism of the conveyor system continues to operate, causing localized heating

of the conveyor belt through contact with the driving drum or other frictional heat source.

© ISO 2018 – All rights reserved v
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SIST EN ISO 20238:2019
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SIST EN ISO 20238:2019
INTERNATIONAL STANDARD ISO 20238:2018(E)
Conveyor belts — Drum friction testing
1 Scope

This document specifies a method of testing to determine the propensity of a conveyor belt to generate

heat flame or glow when held stationary, under a given tension, in surface contact around a rotating

driven steel drum.
It describes means of varying the conveyor belt tension.

NOTE For conveyor belts containing steel reinforcement, it may not be possible to conduct this test in full due

to the inability of the conveyor belt to comply with the requirements of 7.2. In this case, premature termination

according to 7.3 can be necessary.
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 65, Carbon steel tubes suitable for screwing in accordance with ISO 7‑1

ISO 7590, Steel cord conveyor belts — Methods for the determination of total thickness and cover thickness

ISO 9329-1, Seamless steel tubes for pressure purposes — Technical delivery conditions — Part 1: Unalloyed

steels with specified room temperature properties

ISO 9330-1, Welded steel tubes for pressure purposes — Technical delivery conditions — Part 1: Unalloyed

steel tubes with specified room temperature properties
EN 60584-1, Thermocouples — Part 1: EMF specifications and tolerances
3 Terms and definitions
No terms and definitions are listed in this document.

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/
4 Principle

A test piece of conveyor belt, suitably mounted and tensioned, is wrapped halfway around a rotating

steel drum, simulating a stalled belt. The test is continued at specified tensions for a given time period,

or until the belt parts or breaks. The presence, or absence, of flame or glow is noted and reported and

the maximum temperature of the drum is recorded. The test is conducted in still air and/or in moving

air. Two options on arc of contact are given. The reduced arc of contact test (135° of contact) with

increased initial load is considered equivalent to the 180° arc of contact test.
© ISO 2018 – All rights reserved 1
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ISO 20238:2018(E)
5 Apparatus

5.1 Steel drum, of external diameter (210 ± 1) mm mounted on a horizontal axis and capable of being

rotated under all load conditions at (200 ± 5) r/min throughout the test. The outer shell of the drum shall

be manufactured from tube complying with ISO 9329-1 or ISO 9330-1. The surface roughness, Ra, of the

drum surface shall be a maximum of 1,6 μm.

NOTE Experience has shown that motors of between 7,5 kW and 15 kW have proven suitable for maintaining

these conditions, although for smaller motors, a “soft start” can be necessary.
Basic dimensions of the drum, shown in Figure 3, ar
...