Overview
ISO 7365:2012 specifies requirements for the design, operation, performance and acceptance tests of towing winches for deep sea use. It covers winches driven by electric, hydraulic, diesel or steam power and addresses mechanical design, control and safety features. The standard sets performance levels, factory test procedures and a designation system for product models. It does not preclude fibre rope use but does not cover fibre-rope–specific design details.
Key topics and technical requirements
- Design strength limits
- Stalling and holding stresses: allowable stresses ≤ 0.9 × upper yield strength (or 0.2% proof strength).
- Drum load stresses: allowable stresses ≤ 0.4 × upper yield strength (or 0.2% proof strength).
- Drum and rope
- Design-basis rope: eight‑strand steel rope at tensile grades 1 770 or 1 960 N/mm² (per ISO 2408).
- Drum diameter minimum: ≥ 14 × rope diameter.
- Drum capacity/length: accommodate at least 50 m of steel cable on inner layer; flange projection ≥ 1.5 × rope diameter.
- Rope-to-drum attachment: breaking load of attachment limited (see standard text for exact figure).
- Braking and holding
- Electric winch automatic brake must hold 1.25 × drum load and stop drum at max speed without damage.
- Drum (towing) brake must serve as normal and emergency brake; emergency brake capability specified relative to rope strength.
- Clutch must be declutchable; power clutches must allow manual operation.
- Load measurement and alarms
- Continuous load monitors, instantaneous pull recording and overload alarms.
- Audible/visual load alarm at 50% of wire-breaking load.
- Controls and emergency features
- Main control panel on navigation bridge with local emergency stop/release at winch and bridge.
- Emergency drum release must disengage within a max 10 s, operate during power failures and use a single identical control; motor must not auto‑reengage.
- Winch speed adjustable during operation; controls return to stop on release unless agreed otherwise.
- Acceptance/factory tests
- Drum brake holding test, continuous operation under load (15 min), control system utility test, emergency release test.
Applications and users
- Practical uses: specification, procurement, manufacture, installation, testing and acceptance of deep-sea towing winches, and guidance for shipboard safety and operational procedures.
- Primary users: shipbuilders, deck machinery manufacturers, marine architects, classification societies, shipowners/operators, port and offshore service providers, and shipyard testing teams.
Related standards
- ISO 2408 - Steel wire ropes for general purposes
- ISO 3828 - Deck machinery vocabulary and symbols
- ISO 6482 - Warping end profiles for deck machinery
Keywords: towing winches, deep sea, deck machinery, winch design, drum design, load monitoring, emergency release, braking system, acceptance tests.