Overview
ISO 14409:2011 - Ships and marine technology - Ship launching air bags - establishes requirements for the design, manufacture, testing and acceptance of ship launching air bags constructed with synthetic‑tyre‑cord reinforcement layers. The standard defines terms and classification, materials and dimensional tolerances, detailed test methods (gastightness, compression, bearing capacity, bursting, compression–recovery), and rules for marking, documentation, packaging, transport and storage. It is the international reference for specifying reliable, safe air bags used in vessel launching operations.
Key topics and technical requirements
- Scope and definitions: Clear terms for body, head, mouth, rated working pressure, bearing capacity, burst pressure and percentage deformation.
- Classification: Two main types by bearing capacity per metre - QP (ordinary) and QG (high‑bearing capacity) - with models QP3, QP4, QP5 and QG6 (layer counts).
- Geometry and tolerances: Typical diameters (0.8, 1.0, 1.2, 1.5, 1.8 m); length specified by user; dimensional tolerance ±3% at rated working pressure.
- Materials: Construction with outer and inner rubber layers plus one or more synthetic‑tyre‑cord fabric reinforcement layers; materials must be vulcanized firmly.
- Rubber performance (per referenced test methods): tensile strength ≥ 18 MPa, elongation at break ≥ 400%, Shore A hardness 60 ± 10, tear strength ≥ 400 N/cm, compression set and ageing resistance limits, and ozone resistance requirements.
- Reinforcement fabric: Warp density ~ (90 ± 5) cords/100 mm; cord breaking strength > 205 N/cord.
- Testing protocols: Specified ambient conditions (10–35 °C), media (clean compressed air; fresh water for burst test), calibrated instruments. Key tests include:
- Gastightness: pressure loss
