ISO 16625:2025
(Main)Cranes and hoists — Selection of wire ropes, drums and sheaves
Cranes and hoists — Selection of wire ropes, drums and sheaves
This document provides a proof of competence and criteria for the selection of steel wire ropes used in cranes as defined in ISO 4306-1. The influence of the geometry of the rope drive, as well as drum and sheave geometry, are incorporated in the proof of competence. This document does not apply to fibre ropes.
Appareils de levage à charge suspendue et treuils — Choix des câbles, tambours et poulies
General Information
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Standards Content (Sample)
International
Standard
ISO 16625
Second edition
Cranes and hoists — Selection of
2025-02
wire ropes, drums and sheaves
Appareils de levage à charge suspendue et treuils — Choix des
câbles, tambours et poulies
Reference number
© ISO 2025
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Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 2
3.1 Terms and definitions .2
3.2 Symbols .2
4 Running ropes and stationary ropes. 5
4.1 General .5
4.2 Discard criteria .5
4.3 Rope and rope terminations .6
5 Proof of competence of running ropes . 6
5.1 Proof of static strength .6
5.1.1 General .6
5.1.2 Vertical hoisting of loads .6
5.1.3 General rope drives . 12
5.1.4 Limit design rope force . 15
5.2 Proof of fatigue strength .16
5.2.1 General .16
5.2.2 Design rope force .19
5.2.3 Limit design rope force . 22
5.3 Proof of competence for multilayer spooling .27
5.3.1 General .27
5.3.2 Vertical hoisting of loads . 28
5.3.3 General rope drive . 28
5.3.4 Limit design rope force . 29
6 Proof of competence of stationary ropes .30
6.1 Proof of static strength . 30
6.1.1 General . 30
6.1.2 Limit design rope force . 30
6.2 Proof of fatigue strength .31
6.2.1 General .31
6.2.2 Limit design rope force .31
Annex A (normative) Number of relevant bending cycles .33
Annex B (informative) Determination of the maximum tensile force in the ropes of multi-rope
grabs (holding and closing) . .45
Annex C (informative) Comparison of minimum design factor according to ISO 16625:2013 and
safety level according current version .46
Annex D (informative) Selection of a rope by minimum design factor Z .
p
Annex E (informative) Assumed number of hoist ropes l during the design life of a crane .
r
Annex F (informative) Other rope-related design and rope selection aspects .54
Bibliography .66
iii
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).
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Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
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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 96, Cranes, Subcommittee SC 3, Selection of ropes.
This second edition cancels and replaces the first edition (ISO 16625:2013), which has been technically
revised.
The main changes are as follows:
— rope selection has been based on working cycles as opposed to the previous time-based concept;
— different proofs of competence for running ropes (static, fatigue, multilayer spooling) and stationary
ropes (static, fatigue) have been incorporated;
— the substantial innovation of this document lies in a new mathematical approach for the proof of fatigue
strength of running steel wire ropes. A new reference point has been introduced as a characteristic value
for the fatigue strength, from which the S-N curves of the fatigue strength of steel wire ropes at different
D/d-ratios are described;
— additional annexes have been introduced:
— Annex A (normative) Number of relevant bending cycles;
— Annex B (informative) Determination of the maximum tensile force in the ropes of multi-rope grabs
(holding and closing);
— Annex C (informative) Comparison of the minimum design factor according to ISO 16625:2013 and
safety level according current version;
— Annex D (informative) Selection of a rope by minimum design factor Z ;
p
— Annex E (informative) Assumed number of hoist ropes l during life of a crane.
r
This document is intended to be used together with the ISO 4301-1 or other applicable part of the ISO 4301
series, ISO 4309, ISO 8686-1 or applicable part of the ISO 8686 series.
iv
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.
v
International Standard ISO 16625:2025(en)
Cranes and hoists — Selection of wire ropes, drums and sheaves
1 Scope
This document provides a proof of competence and criteria for the selection of steel wire ropes used in
cranes as defined in ISO 4306-1.
The influence of the geometry of the rope drive, as well as drum and sheave geometry, are incorporated in
the proof of competence.
This document does not apply to fibre ropes.
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 2408, Steel wire ropes — Requirements
ISO 4301-1, Cranes — Classification — Part 1: General
ISO 4306-1, Cranes — Vocabulary — Part 1: General
ISO 4309, Cranes — Wire ropes — Care and maintenance, inspection and discard
ISO 8686-1:2012, Cranes — Design principles for loads and load combinations — Part 1: General
ISO 8686-2, Cranes — Design principles for loads and load combinations — Part 2: Mobile cranes
ISO 8686-3, Cranes — Design principles for loads and load combinations — Part 3: Tower cranes
ISO 8686-4, Cranes — Design principles for loads and load combinations — Part 4: Jib cranes
ISO 8686-5, Cranes — Design principles for loads and load combinations — Part 5: Overhead travelling and
portal bridge cranes
ISO 8793, Steel wire ropes — Ferrule-secured eye terminations
ISO 17558, Steel wire ropes — Socketing procedures — Molten metal and resin socketing
ISO 17893, Steel wire ropes — Vocabulary, designation and classification
ISO 20332, Cranes — Proof of competence of steel structures
EN 13411-3, Terminations for steel wire ropes — Safety
...
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