ISO/TS 23624:2021

TECHNICAL ISO/TS
SPECIFICATION 23624
First edition
2021-05
Cranes — Safe use of high-
performance fibre ropes in crane
applications
Appareils de levage a charge suspendue — Utilisation en sécurité des
câbles synthétiques haute performance pour les applications sur les
appareils de levage à charge suspendue
Reference number
©
ISO 2021
© ISO 2021
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ii © ISO 2021 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 HPFR performance considerations . 3
4.1 Responsibilities . 3
4.2 Risk assessment . 3
4.3 Rope . 4
4.3.1 Types of ropes . 4
4.3.2 Selection of ropes . 5
4.4 Proof of competence. 7
4.5 Safety factor at discard for HPFR . 7
5 Crane design considerations . 8
5.1 Termination on the drum . 8
5.2 Termination at load side . 9
5.3 Drum . 9
5.3.1 Lowering limiter . 9
5.3.2 Forces on flange and tube (Multilayer drum) . 9
5.3.3 Shape of grooves on drums .10
5.3.4 Clearance between rope and diameter of drum flange .10
5.3.5 Temperature limits .10
5.4 Sheaves .10
5.4.1 Shape of grooves .10
5.4.2 Material of sheave .10
5.4.3 Minimum D/d ratio .10
5.5 Crane .11
5.5.1 Contact surfaces .11
5.5.2 Fleet angles .11
5.5.3 Substitution on existing design and optimization on new designs .11
5.5.4 Substitution on used cranes .11
6 Qualification testing of HPFR .11
6.1 General .11
6.2 Basic data of HPFR .12
6.2.1 General.12
6.2.2 Minimum breaking strength, MBS .12
6.2.3 Residual breaking strength, RBS .12
6.2.4 Residual lifetime . .12
6.3 Qualification testing .12
6.3.1 General.12
6.3.2 Bending fatigue performance .13
6.3.3 Multilayer spooling performance .13
6.3.4 Tension fatigue performance (rope and termination) .13
6.3.5 Termination performance (Static) .14
6.4 Interpolation of test results .14
7 Information to be provided regarding care, maintenance and inspection .14
7.1 General .14
7.2 Installation of HPFR .14
7.2.1 Stationary ropes .14
7.2.2 Running ropes .14
7.3 Maintenance .15
7.3.1 Maintenance of the rope .15
7.3.2 Maintenance of rope-related parts of the crane .15
7.4 Inspection .15
7.5 Discard criteria .15
Annex A (normative) Selection of ropes .18
Annex B (informative) Qualification testing .22
Annex C (informative) HPFR test report – Spreadsheet .28
Annex D (informative) Example of discard .38
Bibliography .42
iv © ISO 2021 – All rights reserved

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 96, Cranes, Subcommittee SC 3, Selection
of ropes.
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.
Introduction
Recent developments of high-performance fibre ropes (HPFR) made from synthetic fibre have led to
comparable strength with regard to steel wire ropes. The main advantages of using HPFR on cranes
are:
a) light weight (significant weight reduction);
b) no environment pollution by grease (no re-lubrication);
c) easy handling (faster and easier assembly/disassembly);
d) robust spooling (increased tolerance for spooling failures).
The use of HPFR on cranes has already started, however, there is limited experience with HPFR in
comparison to the long-term application of steel wire ropes.
For steel wire ropes, substantial experience over many decades covering both rope selection and discard
criteria exists, which can be found in International Standards (e.g. ISO 16625 and ISO 4309). Currently,
there is no standard available that deals with design and discard criteria for the use of HPFR on cranes.
Therefore, this document has been developed based on the content of the FEM 5.024 guideline.
The FEM 5.024 guideline was developed by the Fédération Européenne de la Manutention (FEM) as
a joint project with various stakeholders in the industry. It is based on first experiences with mobile
cranes and the requirements/limits in some cases can be specific to mobile cranes only.
This document includes additional input from tower crane and electric overhead traveling crane
manufacturers. Adaptation to other crane types or applications can be necessary.
This document reflects the current knowledge about the use of HPFR on cranes.
vi © ISO 2021 – All rights reserved

TECHNICAL SPECIFICATION ISO/TS 23624:2021(E)
Cranes — Safe use of high-performance fibre ropes in
crane applications
1 Scope
This document gives guidance for the safe use of high-performance fibre ropes (HPFR) in crane
applications.
This document also covers winch applications. The mention of crane applications implicitly includes
winch applications.
This document covers performance criteria and the necessary evaluation to enable selection of HPFR
as well as best practice guidelines on procedures, testing and maintenance to safely operate HPFR in
crane applications including provisions for assembly/disassembly.
The performance criteria are related to tasks performed when using cranes as intended, including
assembly/disassembly, operation and required checks and maintenance.
This document does not deal with so-called hybrid ropes which are a combination of steel wire and
high-performance fibres, where the load bearing capability is shared between steel wires and the
high-performance fibre. This document does not deal with HPFR used for high risk applications (e.g.
transport of hot molten metal).
2 Normative references
The following documents are referred to in the text in such a way that some or all 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 2307:2019, Fibre ropes — Determination of certain physical and mechanical properties
ISO 4309:2017, Cranes — Wire ropes — Care and maintenance, inspection and discard
ISO 9554:2019, Fibre ropes — General specifications
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
assembly/disassembly
operations needed to set up/down a crane in a specific configuration or change the configuration
3.2
competent person
designated person, suitably qualified by knowledge and experience, and with the necessary instruction
to ensure that the required operations are carried out correctly
3.3
cyclic bending over sheave
CBOS
condition where a section of rope experiences a repeated straight-bent-straight change of curvature
onto and off a sheave or roller
Note 1 to entry: In a CBOS test, the fibre rope runs around at least one test sheave. A rope pulling force is applied
via an appropriate system. During the test, the rope is running in a constant manner on and off the sheave,
taking the condition straight–bent–straight. A movement straight–bent–straight over a test sheave counts as one
bending cycle for the rope.
3.4
efficiency factor
loss of rope force of a high-performance fibre rope (3.5) when bent over sheaves, resulting in rope pull
differences
3.5
high-performance fibre rope
HPFR
rope based on high-performance fibres, with a high tensile strength, high modulus and low elongation
at break
Note 1 to entry: These fibre ropes have mechanical characteristics in the range of steel wire with regard
to strength per area, axial stiffness and elongation at break [e.g. aromatic polyamide (aramid), high modulus
polyethylene (HMPE), liquid crystal polymer (LCP), see 4.3.1].
3.6
maximum rope pull
MRP
maximum force applied to the rope during design [of the rope drive (3.13)], taking into account dynamic
effects, efficiency of the rope drive, reeving, spread, etc., during operation
3.7
minimum breaking strength
MBS
minimum force achieved by a new rope when tested in accordance with a recognized procedure/test
method
3.8
point of discard
point where the tested failure or wear criterion is achieved considering the residual lifetime (3.10)
3.9
residual breaking strength
RBS
force a used fibre rope achieves at a point in time when tested according to a recognized procedure/test
method
3.10
residual lifetime
remaining lifetime at a point in time, where the attested failure criterion is not yet fully achieved
3.11
actual rope diameter
d
act
diameter of the circle circumscribed about the cross-section of the rope, usually measured under a
given tension and method
[SOURCE: ISO 1968:2004, 5.1.10]
2 © ISO 2021 – All rights reserved

3.12
nominal rope diameter
d
reference value for the diameter of a given high-performance fibre rope (3.5)
[SOURCE: ISO 1968:2004, 5.1.11]
3.13
rope drive
reeving system according to ISO 4306-1, including the drum (actuator) or other actuators, e.g. cylinders
or traction systems
3.14
rope safety factor
n
ratio between breaking strength of the rope and the maximum rope pull (3.6)
3.15
termination
means of connecting the high-performance fibre rope (3.5) to load bearing parts (e.g. crane, winch, hook)
3.16
torsional stiffness
ability of the high-performance fibre rope (3.5) to resist externally induced twist
4 HPFR performance considerations
4.1 Responsibilities
Where a HPFR is installed in a new crane, the crane manufacturer is responsible for the rope drive
design, selection of the rope and instructions for use and maintenance.
The rope manufacturer is responsible for providing correct and complete information regarding the
rope characteristics and providing information regarding maintenance and inspection of the rope in
use.
When a steel wire rope originally installed in a crane is intended to be replaced by a HPFR, an evaluation
of the crane design in general and the rope drive components shall be performed by the crane user,
with the support and approval of the crane manufacturer, to ensure that all the provisions given by the
HPFR manufacturer and this document are fulfilled. The same principle applies when an existing HPFR
is replaced by another type of HPFR. The crane user is responsible for ensuring that the crane is used
and maintained as instructed.
4.2 Risk assessment
Prior to approval for use of HPFR on a crane application, a risk assessment considering the intended use
and any reasonably foreseeable misuse shall be carried out by the manufacturer of the crane application,
identifying potential risks that can impact the safety of the rope in operation (see ISO 12100:2010).
The risk assessment should cover the entire life cycle of the rope including installation, maintenance,
storage and disposal, rope drive, potential environmental conditions and specifics of the application,
including all reasonably expected risks of contact with objects external to the crane. This document
shall be reviewed jointly by both the rope manufacturer and the crane application manufacturer (or
other applicants), in order to identify potential operational and system risks that can affect the safety of
operation. Critical interactions during operation between the rope drive system and HPFR identified in
this analysis shall be documented in the technical files to ensure they are in line with the requirements
of this document and provide suitable safety as determined for mitigation in the risk assessment
process.
Qualification testing of the HPFR shall cover identified critical wear modes to validate that discard
criteria provide the required safety factor. The safety factor shall take into account residual breaking
strength (RBS) in relation to maximum rope pull (MRP) and residual lifetime required at discard
condition of the HPFR.
Where either the HPFR or the rope drive system is intended to change, the risk assessment shall be
reviewed to ensure that critical safety considerations are not changed.
The limits of the machinery and the remaining residual risks, which can result from the risk assessment
analysis, shall be added in the crane’s manual.
4.3 Rope
4.3.1 Types of ropes
The base element of a HPFR is the load bearing fibre. There is a variety of high-performance fibres
available to rope manufacturers, each with different attributes that affect characteristics of the final
rope. Typical materials utilized in HPFR design include amongst others:
a) aromatic polyamide (aramid);
b) high modulus polyethylene (HMPE);
c) polyarylate (liquid crystal polymer, LCP);
d) polybenzoxazole (PBO).
The high-performance fibre is selected by the rope manufacturer based on specific characteristics
inherent to the material including:
a) tensile strength;
b) modulus (axial stiffness);
c) elongation at break;
d) creep characteristics (if applicable);
e) fatigue resistance (bending and tension);
f) coefficient of friction;
g) linear density;
h) environmental resistances [for details see 4.3.2.2 j)].
For further information, see ISO 9554:2019, Table A.1.
The high-performance fibres are combined into larger structures through a process such as twisting,
braiding, winding or a combination of these or other methods. The design of HPFR construction has a
significant impact on the performance of the rope.
Traditional fibres such as polyester, polyamide or polypropylene may be utilized in non-load bearing
structures [e.g. protective covers (jackets), stabilizing cores].
Coatings and other non-fibrous materials may be incorporated into the construction of a HPFR in order
to achieve various performance characteristics.
Various rope constructions can be utilized in the design of a rope. Several common examples are shown
in Figure 1:
— laid in Figure 1 a);
4 © ISO 2021 – All rights reserved

— braided in Figure 1 b);
— cover (jacket over braided rope) in Figure 1 c);
— cover (jacket over parallel fibre) in Figure 1 d).
a) Laid
b) Braided
c) Cover (jacket over braided rope)
d) Cover (jacket over parallel fibre)
Figure 1 — Common rope construction examples
4.3.2 Selection of ropes
4.3.2.1 General
Hoist ropes shall be selected individually for each particular application and shall be made of suitable
materials so that they withstand the intended use. They shall be designed for a period of use, which
shall be at least twice the inspection interval, as specified by the crane manufacturer.
The fibre, rope construction and coatings utilized in the design of a HPFR, as well as the design of the
rope drive, impact the performance of the HPFR in a given application. Selection of a suitable HPFR
shall be the responsibility of the crane manufacturer supported by the rope manufacturer, taking into
consideration the potential operational and system risks of the particular crane application including
the items listed in 4.3.2.2 and 4.3.2.3.
The HPFR discard criteria as per examples shown in Annex D shall be provided by the rope manufacturer
and shall be provided in the manual of the crane.
Where HPFR is used in static (e.g. pendants) or semi-static applications, the rope manufacturer and
crane manufacturer shall agree on designed lifetime and discard criteria, specifically in consideration
of creep elongation, creep rupture, tension-fatigue and dampening.
The list of items given in 4.3.2.2 and 4.3.2.3 is not exhaustive. Additional items given in Annex A shall
be fulfilled.
NOTE Many of the properties listed do not have standard test methods available. The rope manufacturer
needs to show how these properties were determined.
4.3.2.2 Rope characteristics
The rope characteristics shall be provided by the rope manufacturer. The rope characteristics shall
include the standard or test method used to determine each characteristic.
a) Rope basic characteristics:
— nominal rope diameter
— actual rope diameter (initial and in service including tolerances and measurement method);
— length (initial and in service including tolerances);
— rope weight (per metre);
b) efficiency factor;
c) abrasion resistance;
d) resistance to particle ingress;
e) cut resistance;
f) coefficient of friction;
g) fatigue characteristics:
— bending fatigue;
— tension-tension fatigue;
h) load elongation characteristics:
— elongation;
— stiffness (axial, transverse);
— creep;
i) terminations (see 5.1 and 5.2):
— installation methods;
— fatigue characteristics;
j) environmental resistance:
— temperature;
— chemical;
— ultraviolet radiation (UV);
— weathering;
k) discard criteria;
l) rope minimum breaking strength (MBS);
6 © ISO 2021 – All rights reserved

m) twist performance:
— tension-torsion coupling;
— torsional stiffness.
4.3.2.3 Rope drive characteristics
The rope drive characteristics are the responsibility of the crane application manufacturer.
a) Maximum rope pull (MRP);
b) fleet angles;
c) in-service, out of service and storage temperatures;
d) service intervals;
e) efficiency of the rope drive system;
f) sheave, block and drum design:
— roughness;
— corrosion resistance,
— diameter ratio;
— groove profile and system;
— spooling performance (including pre-tensioning, rope pull etc.);
— material;
g) classification (according to ISO 4301-1):
— U-class (total numbers of working cycles),
— Q-class (load spectrum);
— D-class (average displacement of load);
h) average load movements (displacements).
4.4 Proof of competence
The rope drive design shall assure sufficient safety margins on strength and service life until discard
for a given application of a crane. This shall be achieved by the following requirements:
a) the HPFR shall be selected according to the criteria given in 4.3.2; and
b) the competence of the rope drive design shall be determined by a proof of competence, including
proof of static strength and proof of fatigue strength of the HPFR.
This is achieved by a qualification test (see 6.3).
4.5 Safety factor at discard for HPFR
Selection of an appropriate HPFR for specific applications shall take into account a rope safety factor at
discard when assessing suitability for the required lifetime (design lifetime) and specified inspection
frequency.
The safety factor at discard for HPFR shall be determined by the crane manufacturer, considering
performance data from the rope manufacturer and the results of the risk assessment, to ensure a
sufficient safety margin for residual breaking strength and a sufficient residual lifetime at discard.
Inspection intervals of the HPFR drive and in particular of the HPFR shall be determined with regard to
the degradation of the rope during use.
The minimum safety factor at discard, expressed as the ratio of RBS at discard and MRP, and the ratio of
residual lifetime and total lifetime shall be taken from Table 1 and Table 2 for various crane types (see
also 6.3 and 7.5).
Table 1 — Minimum HPFR safety factors for running ropes at discard for various crane types
Crane types Safety factor at discard Residual lifetime
n at discard
%
Winches for pulling purpose only 2,4 60
Hoists (including winches for lifting) 3,0 60
Mobile cranes 3,0 60
Tower cranes 3,0 60
Bridge and gantry cranes 3,0 60
Table 2 — min. HPFR safety factors for stationary ropes at discard for various crane types
Crane types Safety factor at discard Residual lifetime
n at discard
%
Mobile cranes 2,5 60
Tower cranes 2,5 60
Bridge and gantry cranes 2,5 60
NOTE 1 The safety factor at discard differs from the normally used safety factor related to the beginning of
the service-life.
NOTE 2 The various factors consider the risk assessment for different applications and current experience.
NOTE 3 HPFR safety factors and residual lifetimes can be reviewed after gaining future experience.
5 Crane design considerations
5.1 Termination on the drum
The termination on the drum consists of:
a) the drum attachment; and
b) a requisite number of safety wraps.
This termination a) and b) shall be capable of holding at least a rope force equivalent to 80 % of the
safety factor at discard, n, multiplied by the maximum rope pull, F .
MRP
To calculate the required drum attachment strength, Formula (1) shall be used:
F
MRP
Tn ≥×08,  × (1)
drum
μα
e
where
8 © ISO 2021 – All rights reserved

F is the maximum rope pull;
MRP
T is the required drum attachment strength;
drum
n is the required minimum safety factor at discard (see Table 1 and Table 2);
μ is the coefficient of friction for HPFR to drum;
α is the angle of wrap in radians, equivalent to 2π times the number of wraps on the drum.
The coefficient of friction varies with service conditions. Accordingly, testing shall be performed under
the worst (slippery) service conditions (e.g. wet, oily, ice, temperature).
NOTE 1 Current experience indicates a minimum value of friction μ = 0,04.
The HPFR drum attachment a) shall be capable of holding at least 1,2-times the maximum rope pull in
the rope drive. The HPFR fastening, e.g. wedge and socket, shall not become detached even when the
rope pull is zero.
The termination of the HPFR shall be selected taking into account the rope and drum contours. The
drum attachment a) shall be easily accessible for maintenance and replacement of the HPFR.
NOTE 2 Over time the efficiency of the termination can decrease, for example in a clamp. In such cases re-
application of a tightening force is necessary.
5.2 Termination at load side
The end termination at the load side shall be capable of holding at least a rope force equivalent to 80 %
of the safety factor at discard, n, multiplied by the maximum rope pull, F , as given in Formula (2).
MRP
Tn ≥×08,  ×F (2)
load MRP
where
T is the required load side strength;
load
F is the maximum rope pull;
MRP
n is the required minimum safety factor at discard (see Table 1 and Table 2).
5.3 Drum
5.3.1 Lowering limiter
The hoisting system shall be fitted with a lowering limiter. The lowering limiter shall ensure that the
minimum engagement (requisite safety wraps) of the HPFR with the drum is maintained at all times
during operation.
5.3.2 Forces on flange and tube (Multilayer drum)
HPFR behave differently than steel wire ropes whilst spooling on a multilayer drum and can cause
significantly increased forces acting on drum flange and tube. These forces shall be taken into account
where multilayer drums are equipped with HPFR. The calculation should be verified by practical
testing.
NOTE A HPFR is more compressed during work than a steel wire rope, flattening the rope and causing
increased lateral forces acting on the flange. The difference in axial stiffness can also increase the forces acting
on the drum tube.
5.3.3 Shape of grooves on drums
Drum grooves surfaces shall be smooth and free of surface irregularities that can damage the HPFR.
Peaks and edges shall be rounded to reduce damage of the HPFR due to cutting. System grooving,
helical grooving or flat patterns may be used depending on the design of the HPFR and drum.
As HPFR tend to flatten when compressed on the drum, the cross-section for rope stored on a drum is
typically not circular. This effect shall be taken into account.
The groove pitch shall provide sufficient clearance between adjacent HPFR turns on the drum, taking
into account the HPFR diameter tolerance.
The groove of grooved drums shall fit to the type of HPFR as given by the HPFR manufacturer.
The rope manufacturer shall be consulted regarding the anticipated changes in width of the rope under
the compressive loading specific to a given application prior to optimizing the groove profile for a given
HPFR. The amount of rope ovalization depends on many factors including high-performance synthetic
fibres used, rope construction and tension profile common in the application.
NOTE The minimum groove diameter to be chosen in relation to the nominal rope diameter strongly
depends on the effects of bedding-in a new rope.
5.3.4 Clearance between rope and diameter of drum flange
Where HPFR is used in hoisting mechanism, measures on drums shall be provided, e.g. flanged drum
end plates, frame/housing and rope guides, which prevent the ropes from running off the ends of the
rope drums.
Flanged drum end plates shall protrude beyond the rope wound on the drum at the top layer by at least
1,5 times the bedded-in HPFR diameter with the rope spooled on the drum with minimum (functional)
rope pull.
5.3.5 Temperature limits
HPFR acts as a thermal insulation when compared with steel wire ropes spooled on a drum with internal
gearbox. This effect shall be taken into account when designing the drum system. Peak temperatures
shall not exceed the allowable temperature limits for the HPFR used, taking into account the maximum
permitted environmental temperatures.
5.4 Sheaves
5.4.1 Shape of grooves
Sheave grooves shall be rounded to form a close-fitting saddle as recommended by the rope
manufacturer, based on the design of the HPFR. The opening of the sheave should be wide enough to
easily allow rope entry at any anticipated fleet angle with an opening angle between 45° and 60°.
Grooves of sheaves shall be smooth and free from surface defects liable to damage the HPFR. The peaks/
edges shall be rounded to reduce damage of the HPFR due to cutting.
5.4.2 Material of sheave
Sheaves for use with HPFR may be made of either metallic or polymer materials. Consult the rope
manufacturer on recommended materials and surface requirements.
5.4.3 Minimum D/d ratio
The minimum D/d ratio chosen shall be at least as large as the ratio proven in qualification CBOS testing,
where D is the sheave pitch diameter and d is the nominal rope diameter.
10 © ISO 2021 – All rights reserved

Reliability of discard criteria shall be explicitly proven for D/d ratios used in the application (see rope
qualification testing in Annex B).
NOTE Current experience indicates a typical D/d value of 20. A lower value can reduce the lifetime.
5.5 Crane
5.5.1 Contact surfaces
All surfaces where contact between HPFR and structural parts is foreseen shall be free from sharp
edges, defects and corrosion. Surface roughness values shall be maintained as specified by crane and/
or rope manufacturer.
Surface roughness should not exceed ISO 1302:2002 roughness class N9 (equivalent R 6,3 μm). Greater
a
classes significantly accelerate the rate of abrasion in HPFR and reduce service lifetime.
NOTE All surfaces need to be checked for potential contact with the loaded or unloaded HPFR for in- and
out-of-service and transport/travel and during assembly.
5.5.2 Fleet angles
The maximum fleet angle of running ropes shall be kept under 2,5°, unless the risk assessment allows
small deviations to higher values.
Any fleet angle influences the lifetime of the rope. The lifetime of a HPFR is significantly decreased if
the fleet angle of 2,5° is exceeded.
Potential influence of fleet angle on twist (rotation) of the HPFR shall be checked during qualification
testing (see Annex B).
5.5.3 Substitution on existing design and optimization on new designs
When intended to fit HPFR on new cranes designed originally for use with steel wire rope, an evaluation
of the crane design shall be performed by the crane manufacturer to ensure all instructions given by
the HPFR manufacturer and this document are fulfilled.
In addition, the crane manufacturer shall review other criteria relevant for safety, e.g. rigid body
stability of the crane, which can be related to the weights of the installed rope.
Optimization of the mechanical systems specifically for use with HPFR is preferable whenever feasible.
Following a process of designing the crane systems specifically for use with HPFR allows for full
realization of the benefits provided by the technology.
5.5.4 Substitution on used cranes
When a steel wire rope originally installed in a crane is intended to be replaced by a HPFR, an
evaluation of the crane design and the rope drive components shall be performed by the crane user
with the support and approval of the crane manufacturer to ensure all instructions given by the HPFR
manufacturer and this document are fulfilled. Critical and worn out parts need to be repaired or
exchanged prior to the use of HPFR on the crane.
6 Qualification testing of HPFR
6.1 General
The qualification testing shall demonstrate fitness for purpose for a HPFR drive design for the
considered application and validate the discard criteria of the HPFR.
To approve a HPFR for use in a specific application, the rope manufacturer and/or the crane
manufacturer shall determine at least the data of 6.2 to 6.4. They shall also ensure safe use and fitness
for purpose of the HPFR as identified in the risk assessment.
6.2 Basic data of HPFR
6.2.1 General
For a HPFR in a specific application, the following basic data at least shall be determined by testing:
a) minimum breaking strength, MBS;
b) residual breaking strength, RBS at discard;
c) residual lifetime at discard.
6.2.2 Minimum breaking strength, MBS
The minimum breaking strength shall be stated by the HPFR manufacturer. The MBS shall be verified
through testing in accordance with ISO 2307:2019.
6.2.3 Residual breaking strength, RBS
The most damaged section of the rope shall be the area of interest for this testing. Therefore, it shall be
placed at the centre of the free rope length of the test specimen. The rope residual breaking strength
shall be verified through testing in accordance with ISO 2307:2019, but changing the pre-tensioning
force during bedding-in procedure from 50 % MBS to 20 % MBS.
6.2.4 Residual lifetime
The most damaged section of the rope shall be the area of interest for this testing. Therefore, it shall
be placed at the location showing the most degradation during continued testing of the test specimen.
The rope residual lifetime shall be verified through continued testing of the sample in a manner that
simulates the same wear pattern which resulted in the observed discard criteria being achieved (e.g.
cyclic bend over sheave, abrasion with a substrate, etc.) (see also 6.3).
6.3 Qualification testing
6.3.1 General
Testing included during qualification of the HPFR shall be determined based on the application specific
considerations identified during the risk assessment. These tests shall simulate the rope damaging
wear modes that occur through use in the designated operation. Qualification testing shall be designed
to identify the discard criteria and ensure that they are observable while the required safety margin
remains.
The combined effect of the factors identified under 4.3.2 has a significant impact on the HPFR lifetime.
Therefore, qualification testing of the rope drive is required taking into account these factors and a
combination of these factors. The requirements and test scope of this program shall be established
between crane and rope manufacturer. A recommended practice is given in Annex B.
The samples for qualification testing shall be chosen to give sufficient statistical evidence (at least 3
samples, except if the deviation in the first two test results is less than 25 % of the higher lifetime, then
two tests are sufficient).
NOTE 1 For guidance, see Annex B.
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Where applicable, test samples for evaluation of the safety factors should be taken from both the area
of discard as well as from other critical areas. The following tests shall be included in the qualification
testing for applications that are identified as having the corresponding wear modes.
NOTE 2 For an example report of results, see Annex C.
6.3.2 Bending fatigue performan
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