ISO 11515:2022

Overview

ISO 11515:2022 - "Gas cylinders - Refillable composite reinforced tubes of water capacity between 450 l and 3000 l - Design, construction and testing" defines international minimum requirements for the design, manufacture, inspection and performance testing of large refillable composite gas tubes. The standard covers Type 2 (hoop-wrapped), Type 3 (fully-wrapped) and Type 4 (fully-wrapped, non-load-sharing liner) composite tubes with water capacities from 450 l to 3 000 l, intended for compressed or liquefied gases at test pressures up to 1 600 bar and a design life of at least 15 years. ISO 11515:2022 applies for expected service temperatures between −40 °C and +65 °C. Type 4 tubes manufactured to this document are explicitly not intended for toxic, oxidizing or corrosive gases.

Key topics and technical requirements

• Materials: Requirements for liner materials and composite overwraps using carbon fibre, aramid fibre, glass fibre (or mixtures) in a matrix.
• Design & manufacture: Design submission, manufacturing controls and considerations for mounting and assembly stresses.
• Type approval: Prototype testing, new-design approval, and procedures for design variants.
• Extensive test program, including (but not limited to):
  • Hydraulic proof pressure and volumetric expansion tests
  • Liner burst and full tube burst tests
  • Ambient and environmental cycle testing
  • Flaw detection and ultrasonic inspection (see Annex C)
  • Blunt impact, high-velocity impact (gunfire) and fire resistance tests
  • Accelerated stress-rupture, gas cycle, permeability and leak tests
  • Coatings, salt spray and acid environment tests; glass transition and resin shear strength
• Manufacturing inspection: Batch tests, liner and overwrap acceptance criteria, and handling of failures.
• Marking & documentation: Required tube marking, type approval certificates and test reporting (Annexes A and B).

Practical applications and who uses ISO 11515:2022

ISO 11515:2022 is used where large-capacity refillable composite tubes are required for storage and conveyance of gases, including:

• Industrial gas suppliers and wholesalers
• Cylinder and composite tube designers and manufacturers
• Transport integrators using battery banks, ISO modules, trailers, skids or MEGCs
• Test laboratories and certification bodies performing type approval and batch testing
• Regulatory authorities and safety engineers referencing UN Model Regulations compliance

Adoption of ISO 11515 helps ensure consistent safety, performance, and international acceptance of composite gas tubes across supply chains.

Related standards

• ISO 10286 (Gas cylinders - Vocabulary)
• ISO 7866 (Aluminium refillable cylinders)
• ISO 9809 series (seamless steel gas cylinders/tubes)
• ISO 9712 (NDT personnel qualification)
• Other referenced test standards (e.g., ISO 9227 salt spray)

Keywords: ISO 11515:2022, gas cylinders, composite tubes, Type 2, Type 3, Type 4, design, construction, testing, refillable, 450–3000 l, 1600 bar, carbon fibre, aramid, glass fibre.