Overview
ISO 18692-4:2023 - "Fibre ropes for offshore stationkeeping - Part 4: Polyarylate" defines the main characteristics and test methods for polyarylate fibre ropes used in offshore stationkeeping and mooring applications. It replaces ISO/TS 19336:2015 and supplements the general requirements in ISO 18692‑1:2018, providing material qualification, mechanical requirements, and type-testing protocols specific to polyarylate cores.
Key topics and requirements
- Material specification
- Rope core fibres must be polyarylate with an average tenacity ≥ 1.8 N/tex and core tenacity ≥ 0.90 N/tex (measured per ISO 18692‑1).
- Hydrolysis resistance: residual fibre strength ≥ 90% after immersion (2 weeks at 80 °C or equivalent accelerated conditions).
- Mechanical performance
- Minimum breaking strength (MBS): values are specified per reference number (rope diameter) in Table 1 of the standard.
- Axial compression fatigue: ropes must demonstrate residual strength ≥ 95% of MBS after the Annex B test procedure for axial compression fatigue.
- Cyclic loading endurance: residual strength after cyclic loading must be ≥ 80% of MBS.
- Torque properties: rope construction shall achieve torque-neutral or torque-matched behavior as defined in ISO 18692‑1.
- Construction and protection
- Core particle ingress protection, protective cover thickness, and rope layout follow ISO 18692‑1 provisions.
- Testing and certification
- Detailed type-test methods, sample counts, test machine controls, and reporting requirements are specified. Testing of current production, marking, labelling, packaging, and certification follow ISO 18692‑1.
Practical applications and users
- Target users:
- Rope manufacturers and textile engineers developing high‑performance polyarylate mooring lines.
- Offshore engineers and mooring system designers selecting stationkeeping ropes for floating structures, platforms, and FPSOs.
- Testing laboratories, classification societies, and procurement teams verifying compliance and issuing certifications.
- Practical value:
- Ensures reliable long‑term performance of polyarylate ropes under compression, cyclic loading, seawater exposure and particle ingress.
- Provides objective acceptance criteria (MBS, core tenacity, fatigue and hydrolysis resistance) to support safe mooring design and supplier qualification.
- Harmonizes manufacturer testing and certification for global offshore operations.
Related standards
- ISO 18692‑1:2018 - General specification for fibre ropes for offshore stationkeeping (referenced throughout).
- ISO 1968 - Fibre ropes and cordage vocabulary.
- ISO 9080 - (referenced for accelerated ageing/test-time equivalence).
Keywords: ISO 18692-4:2023, polyarylate fibre ropes, offshore stationkeeping, axial compression fatigue, minimum breaking strength, rope testing, mooring lines, particle ingress protection.
