EN IEC 60793-1-31:2019

Optical fibres - Part 1-31: Measurement methods and test procedures - Tensile strength

This part of IEC 60793 provides values of the tensile strength under dynamic loading of optical fibre samples. The method tests individual lengths of uncabled and unbundled glass optical fibre. Sections of fibre are broken with controlled increasing stress or strain that is uniform over the entire fibre length and cross section. The stress or strain is increased at a nominally constant rate until breakage occurs. The distribution of the tensile strength values of a given fibre strongly depends on the sample length, loading velocity and environmental conditions. The test can be used for inspection where statistical data on fibre strength is required. Results are reported by means of statistical quality control distribution. Normally, the test is carried out after temperature and humidity conditioning of the sample. However, in some cases, it can be sufficient to measure the values at ambient temperature and humidity conditions. This method is applicable to categories A1, A2, and A3, and classes B and C optical fibres. The object of this document is to establish uniform requirements for the mechanical characteristic: tensile strength.

Lichtwellenleiter - Teil 1-31: Messmethoden und Prüfverfahren - Zugfestigkeit

Fibres optiques - Partie 1-31: Méthodes de mesure et procédures d’essai - Résistance à la traction

IEC 60793-1-31:2019 donne les valeurs de résistance à la traction des échantillons de fibre optique, soumis à une charge dynamique. Cette méthode soumet à essai des longueurs individuelles de fibre optique en verre, non câblées et non groupées en faisceau. Des sections de fibre sont rompues en les soumettant à une contrainte ou une déformation croissante et contrôlée, uniforme sur toute la longueur et la section transversale de la fibre. La contrainte ou la déformation augmente à une vitesse nominalement constante jusqu’à ce que la rupture se produise. La distribution des valeurs de résistance à la traction pour une fibre donnée dépend étroitement de la longueur des échantillons, de la vitesse d’application de la force et des conditions d’environnement. L’essai peut s’appliquer à titre d’examen lorsque des données statistiques sur la résistance des fibres sont exigées. Les résultats sont déclarés sous forme d’une distribution statistique de contrôle de qualité. Habituellement, l’essai est réalisé après un conditionnement en température et en humidité de l’échantillon. Cependant, dans certains cas, la mesure des valeurs à la température et à l’humidité ambiantes peut être suffisante. Cette méthode s’applique aux fibres optiques de catégories A1, A2 et A3, et de classes B et C. L’objet du présent document est de déterminer des exigences uniformes relatives à la caractéristique mécanique: la résistance à la traction. Cette troisième édition annule et remplace la deuxième édition parue en 2010. Cette édition constitue une révision technique. Cette édition inclut les modifications suivantes par rapport à l’édition précédente: a) correction des Formules (3b) et (4b) et renumérotation des formules. Mots clés : résistance à la traction des échantillons de fibre optique

Optična vlakna - 1-31. del: Metode merjenja in preskusni postopki - Natezna trdnost (IEC 60793-1-31:2019)

Ta del standarda IEC 60793 podaja vrednosti natezne trdnosti pri dinamični obremenitvi vzorcev optičnih vlaken. Metoda preskuša posamezne dolžine nevezanih in ločenih steklenih optičnih vlaken. Odseke vlaken se poskuša prelomiti z nadzorovano naraščajočo napetostjo ali obremenitvijo, ki je enakomerna po celotni dolžini in preseku vlaken. Napetost ali obremenitev se povečujeta pri nominalno konstantni hitrosti, dokler se vlakno ne zlomi.
Porazdelitev vrednosti natezne trdnosti določenega vlakna je zelo odvisna od dolžine vzorca, hitrosti obremenjevanja in okoljskih pogojev. Preskus je mogoče uporabiti v primerih, kjer so potrebni statistični podatki o trdnosti vlaken. Rezultati so opisani s pomočjo statistične porazdelitve v sklopu nadzora kakovosti. Običajno se preskus opravi po obdelavi vzorca pri izbrani temperaturi in vlažnosti. V nekaterih primerih pa je lahko dovolj, da se izmerijo vrednosti pri sobni temperaturi in vlažnosti.
Ta metoda se uporablja za kategorije optičnih vlaken A1, A2 in A3 ter razreda B in C. Cilj tega dokumenta je vzpostaviti enotne zahteve za mehansko lastnost – natezno trdnost.

General Information

• Status: Published
• Publication Date: 04-Apr-2019
• Withdrawal Date: 12-Mar-2022
• ICS: 33.180.10 - Fibres and cables
• Technical Committee: CLC/TC 86A - Optical fibres and optical fibre cables
• Drafting Committee: IEC/SC 86A - IEC_SC_86A
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 05-Apr-2019
• Completion Date: 05-Apr-2019
• Ref Project: SIST EN IEC 60793-1-31:2019 - Optical fibres - Part 1-31: Measurement methods and test procedures - Tensile strength (IEC 60793-1-31:2019)

Relations

• Replaces: EN 60793-1-31:2010 - Optical fibres - Part 1-31: Measurement methods and test procedures - Tensile strength
• Effective Date: 12-Apr-2019

Overview

EN IEC 60793-1-31:2019 - "Optical fibres - Part 1-31: Measurement methods and test procedures - Tensile strength" defines a standardized method to measure the tensile strength of uncabled, unbundled glass optical fibre under dynamic loading. The method applies a nominally constant increase in stress or strain until breakage, records failure stress, and reports results using statistical quality-control distributions (commonly Weibull analysis). Tests normally include temperature and humidity conditioning; results depend strongly on gauge length, loading (stress/strain) rate, and environmental conditions.

Key topics and requirements

• Scope and applicability
  • For uncabled/unbundled glass optical fibres in categories A1, A2, A3 and classes B and C.
  • Intended for fibres with median fracture stress typically > 3.1 GPa (0.5 m gauge at 25 %/min); not suitable where precision is insufficient.
• Test principle
  • Apply uniformly increasing stress or strain at a nominally constant rate until fibre failure; measure force at break.
• Sample preparation
  • Defined gauge lengths (shorts up to ~1 m; longs 10–20 m) and sample sizes (typical 15–30).
  • Environmental conditioning (temperature and relative humidity) is normally required.
• Apparatus and grips
  • Guidance on gripping methods (e.g., capstan designs, translation/rotating systems) to avoid slippage artifacts.
  • Requirement for force measurement and control of loading rate (stress/strain rate).
• Data analysis and reporting
  • Conversion of load to failure stress and preparation of Weibull plots.
  • Reporting using statistical quality control parameters and full test details (gauge length, strain rate, environment, sample size).
• Limitations
  • Destructive test - not a substitute for production proof-testing.
  • Results are environment- and length-dependent; no universal extrapolation model across environments.

Practical applications and users

• Fibre manufacturers - incoming/outgoing quality control, process monitoring, and product characterization.
• Test laboratories - standardized tensile testing for certification, R&D validation, and inter-lab comparisons.
• R&D and reliability engineers - failure-mode analysis, lifetime/reliability projections (in conjunction with IEC TR 62048).
• Procurement and specifications - defining contractual tensile strength requirements and acceptance criteria.
• Standards bodies and regulators - harmonization and conformity assessment within IEC/CENELEC frameworks.

Related standards

• IEC 60793 series (optical fibres measurement methods)
• IEC 60793-1-20 (fibre geometry)
• IEC TR 62048 (reliability projection using failure stress distributions)
• EN IEC 60793-1-31 is the CENELEC-harmonized version of IEC 60793-1-31:2019

Keywords: EN IEC 60793-1-31:2019, optical fibres tensile strength, tensile testing, measurement methods, dynamic loading, Weibull analysis, gauge length, strain rate, environmental conditioning.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2019
Nadomešča:
SIST EN 60793-1-31:2010
Optična vlakna - 1-31. del: Metode merjenja in preskusni postopki - Natezna
trdnost (IEC 60793-1-31:2019)
Optical fibres - Part 1-31: Measurement methods and test procedures - Tensile strength
(IEC 60793-1-31:2019)
Lichtwellenleiter - Teil 1-31: Messmethoden und Prüfverfahren - Zugfestigkeit (IEC
60793-1-31:2019)
Fibres optiques - Partie 1-31 : Méthodes de mesure et procédures d’essai - Résistance à
la traction (IEC 60793-1-31:2019)
Ta slovenski standard je istoveten z: EN IEC 60793-1-31:2019
ICS:
33.180.10 (Optična) vlakna in kabli Fibres and cables
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60793-1-31

NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2019
ICS 33.180.10 Supersedes EN 60793-1-31:2010
English Version
Optical fibres - Part 1-31: Measurement methods and test
procedures - Tensile strength
(IEC 60793-1-31:2019)
Fibres optiques - Partie 1-31: Méthodes de mesure et Lichtwellenleiter - Teil 1-31: Messmethoden und
procédures d'essai - Résistance à la traction Prüfverfahren - Zugfestigkeit
(IEC 60793-1-31:2019) (IEC 60793-1-31:2019)
This European Standard was approved by CENELEC on 2019-03-13. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60793-1-31:2019 E

European foreword
The text of document 86A/1908/FDIS, future edition 3 of IEC 60793-1-31, prepared by SC 86A "Fibres
and cables" of IEC/TC 86 "Fibre optics" was submitted to the IEC-CENELEC parallel vote and
approved by CENELEC as EN IEC 60793-1-31:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2019-12-13
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-03-13
document have to be withdrawn
This document supersedes EN 60793-1-31:2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 60793-1-31:2019 was approved by CENELEC as a
European Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60793-1-21:2001 NOTE Harmonized as EN 60793-1-21:2002 (not modified)
IEC 60793-2-10:2017 NOTE Harmonized as EN 60793-2-10:2017 (not modified)
IEC 60793-2-20:2015 NOTE Harmonized as EN 60793-2-20:2016 (not modified)
IEC 60793-2-30:2015 NOTE Harmonized as EN 60793-2-30:2015 (not modified)
IEC 60793-2-40:2015 NOTE Harmonized as EN 60793-2-40:2016 (not modified)
IEC 60793-2-50:2015 NOTE Harmonized as EN 60793-2-50:2016 (not modified)
IEC 61649:2008 NOTE Harmonized as EN 61649:2008 (not modified)

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60793-1-20 -  Optical fibres - Part 1-20: Measurement EN 60793-1-20 -
methods and test procedures - Fibre geometry

IEC 60793-1-31 ®
Edition 3.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical fibres –
Part 1-31: Measurement methods and test procedures –Tensile strength

Fibres optiques –
Partie 1-31: Méthodes de mesure et procédures d’essai –Résistance à la traction

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.10 ISBN 978-2-8322-6529-1

– 2 – IEC 60793-1-31:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Hazards . 7
5 Apparatus . 8
5.1 General . 8
5.2 Gripping the fibre at both ends . 8
5.3 Sample support . 8
5.4 Stretching the fibre . 8
5.5 Measuring the force at failure . 9
5.6 Environmental control equipment . 9
6 Sample preparation . 10
6.1 Definition . 10
6.2 Sample size and gauge length . 10
6.3 Auxiliary measurements . 11
6.4 Environment . 11
7 Procedure . 11
7.1 Preliminary steps . 11
7.2 Procedure for a single specimen . 11
7.3 Procedure for completing all samples for a given nominal strain rate . 12
8 Calculations . 12
8.1 Conversion of tensile load to failure stress . 12
8.2 Preparation of a Weibull plot . 13
8.3 Computation of Weibull parameters . 13
9 Results . 14
9.1 Details to be reported . 14
9.2 Details to be recorded . 15
10 Specification information . 15
Annex A (informative) Typical testing apparatus of tensile strength under dynamic
loading . 16
Annex B (informative) Guidelines on gripping the fibre . 18
Annex C (informative) Guidelines on stress rate . 22
Bibliography . 24

Figure 1 – Bimodal tensile strength Weibull plot for a 20 m gauge length test set-up at
5 %/min strain rate . 10
Figure A.1 – Capstan design . 16
Figure A.2 – Translation test apparatus . 16
Figure A.3 – Rotating capstan apparatus . 17
Figure A.4 – Rotating capstan apparatus for long lengths . 17
Figure A.5 – Ganged rotating capstan tester . 17
Figure B.1 – Gradual slippage. 18

IEC 60793-1-31:2019 © IEC 2019 – 3 –
Figure B.2 – Irregular slippage . 18
Figure B.3 – Sawtooth slippage . 19
Figure B.4 – Acceptable transfer function . 19
Figure B.5 – Typical capstan . 20
Figure B.6 – Isostatic compression . 20
Figure B.7 – Escargot wrap . 21
Figure C.1 – System to control stress rate . 22
Figure C.2 – Time variation of load and loading speed . 23

– 4 – IEC 60793-1-31:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRES –
Part 1-31: Measurement methods and test procedures –
Tensile strength
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC
Publication(s)"). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60793-1-31 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This third edition cancels and replaces the second edition published in 2010. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) correction of Formulae (3b) and (4b) and renumbering of formulae.

IEC 60793-1-31:2019 © IEC 2019 – 5 –
The text of this International Standard is based on the following documents:
FDIS Report on voting
86A/1908/FDIS 86A/1926/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60793 series, published under the general title Optical fibres, can
be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 60793-1-31:2019 © IEC 2019
INTRODUCTION
Failure stress distributions can be used to predict fibre reliability in different conditions.
IEC TR 62048 shows mathematically how this can be done. To complete a given reliability
projection, the tests used to characterize a distribution are controlled for the following:
• population of fibre, for example coating, manufacturing period, diameter;
• gauge length, i.e. length of section that is tested;
• stress or strain rates;
• testing environment;
• preconditioning or aging treatments;
• sample size.
This method measures the strength of optical fibre at a specified constant strain rate. It is a
destructive test, and is not a substitute for proof-testing.
This method is used for those typical optical fibres for which the median fracture stress is
greater than 3,1 GPa (450 kpsi ) in 0,5 m gauge lengths at the highest specified strain rate of
25 %/min. For fibres with lower median fracture stress, the conditions herein have not
demonstrated sufficient precision.
Typical testing is conducted on "short lengths", up to 1 m, or on "long lengths", from 10 m to
20 m with sample size ranging from 15 to 30.
The test environment and any preconditioning or aging are critical to the outcome of this test.
There is no agreed upon model for extrapolating the results for one environment to another
environment. For failure stress at a given stress or strain rate, however, as the relative
humidity increases, failure stress decreases. Both increases and decreases in the measured
strength distribution parameters have been observed as the result of preconditioning at
elevated temperature and humidity for even a day or two.
This test is based on the theory of fracture mechanics of brittle materials and on the power-
law description of flaw growth (see IEC TR 62048). Although other theories have been
described elsewhere, the fracture mechanics based on power-law theory is the most generally
accepted.
A typical population consists of fibre that has not been deliberately damaged or
environmentally aged. A typical fibre has a nominal diameter of 125 mm, with a 250 mm or less
diameter acrylate coating. Default conditions are given for such typical populations. Non-
typical populations might include alternative coatings, environmentally aged fibre, or
deliberately damaged or abraded fibre. Guidance for non-typical populations is also provided.

__________
kpsi = kilopounds per square inch.

IEC 60793-1-31:2019 © IEC 2019 – 7 –
OPTICAL FIBRES –
Part 1-31: Measurement methods and test procedures –
Tensile strength
1 Scope
This part of IEC 60793 provides values of the tensile strength under dynamic loading of
optical fibre samples. The method tests individual lengths of uncabled and unbundled glass
optical fibre. Sections of fibre are broken with controlled increasing stress or strain that is
uniform over the entire fibre length and cross section. The stress or strain is increased at a
nominally constant rate until breakage occurs.
The distribution of the tensile strength values of a given fibre strongly depends on the sample
length, loading velocity and environmental conditions. The test can be used for inspection
where statistical data on fibre strength is required. Results are reported by means of
statistical quality control distribution. Normally, the test is carried out after temperature and
humidity conditioning of the sample. However, in some cases, it can be sufficient to measure
the values at ambient temperature and humidity conditions.
This method is applicable to categories A1, A2, and A3, and classes B and C optical fibres.
The object of this document is to establish uniform requirements for the mechanical
characteristic: tensile strength.
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.
IEC 60793-1-20, Optical fibres – Part 1-20: Measurement methods and test procedures –
Fibre geometry
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:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Hazards
This tes
...