Overview
ISO 4568:2021 - Ships and marine technology - Sea-going vessels - Windlasses and anchor capstans - specifies requirements for the design, construction, safety, performance and acceptance testing of windlasses and anchor capstans fitted to sea‑going vessels. The standard covers machines with electric, hydraulic, pneumatic or external drives and defines six equipment types (symmetrical double, single, single units, capstans, and double with connecting shaft). It is essential for designers, manufacturers, shipyards and operators who need to ensure compliant anchoring and deck‑machinery performance.
Key topics and technical requirements
- Scope & equipment types: Types 1–6 (symmetrical double, single, single unit, anchor capstans, double with connecting shaft) and drive options (electric, hydraulic, pneumatic, external).
- Design and construction: Chain cable compatibility with ISO 1704; cable‑lifter design (minimum five snugs); optional warping ends and placement; mooring winch integration (refer ISO 3730).
- Strength & materials: Stress limits for pressed parts relative to material yield (examples in standard: 40 %, 80 %, 95 % thresholds for different conditions).
- Braking systems:
- Electric windlasses require fail‑safe brakes capable of holding 1.5× the working load.
- Non‑electric drives require a suitable fail‑safe system holding at least 1.3× the working load.
- Cable‑lifter hand brakes must control the holding load and be declutchable; detailed human‑factor limits (e.g., hand wheel forces - max 160 N during casting; max 750 N when holding).
- Control braking systems and emergency stops: remote quick‑acting stops that remove power and apply brakes.
- Performance & acceptance testing: Procedures for verifying working load, overload pull, brake performance, speed control and emergency stop functionality.
- Operational requirements: Speed control, protection against torque/shock, remote control locations, and marking/designation rules.
Applications - who uses ISO 4568:2021
- Shipbuilders and naval architects for specifying and integrating windlasses and capstans during design.
- Deck machinery manufacturers for product development, testing and CE/conformity documentation.
- Shipowners, operators and shipyards for procurement, installation, commissioning and acceptance testing.
- Classification societies and flag administrations for compliance checks and survey guidance.
- Maintenance teams for safe operation, repair criteria and replacement part specifications.
Related standards
- ISO 3730 - Mooring winches (for combined windlass/mooring winch systems)
- ISO 1704 - Stud‑link anchor chains
- ISO 3828 - Deck machinery vocabulary and symbols
- ISO 6482 - Warping end profiles
- ISO 7825 - Deck machinery general requirements
- IEC 60092 / IEC 60529 - Ship electrical installations and enclosure protection
- ISO 4413 - Hydraulic safety requirements
ISO 4568:2021 is a practical, safety‑focused standard for reliable anchoring machinery on sea‑going vessels and should be used alongside applicable classification society rules and flag‑state regulations.
