Thermal protection equipment  [ Return towards  Flight equipment for storage  ]

The main cryogenic tanks on the Ariane are insulated externally using closed-cell foam bonded straight onto the aluminum structure. This material combines the following advantages: low density, low thermal conductivity, easy shaping, can be bonded straight onto the aluminum structure, leak tightness (closed cells) to prevent any risk of cryo-pumping on the launch pad and resistance to aerothermal fluxes during launcher ascent.
The same type of material is also used to insulate lines or equipment of complex shape.

The Liquid Helium Sub-System on Ariane V is insulated using vacuum Multi-Layer Insulation (MLI). Installing insulation of this kind is tricky and critical and a machine had to be specially developed to wind the MLI automatically.

A Dacron^TM felt coated with an aluminized film is also used on Ariane to insulate internal cavities. Such insulation is very light and also very easy to use.

The cryogenic tanks of the third stage of Ariane 4 were separated by a vacuum honeycomb common bulkhead, which combined high static and dynamic structural strength with excellent insulation performance. A similar bulkhead is currently being developed for future versions of the ARIANE 5 rocket.

• Maturity: the above insulation systems have flown on Ariane and have thereby demonstrated their effectiveness and their sturdiness.
• Adaptability: the diversity of the solutions on offer affords a response to a maximum number of applications.
• Air Liquide Expertise: Air Liquide can design and proportion the insulation best suited to customer requirements. A testing area is used to conduct structural and heat tests on insulation systems in a cryogenic environment. Air Liquide DTA is also able to shape and prepare insulation at the request of the customer in accordance with quality requirements in the space industry.

• Reduced density
• Low thermal conductivity

• Closed-cell foam, compatible with aerothermal fluxes:
  density: 44 +/- 5 kg/m3 before thermoforming
  thermal conductivity: 33 mW/m.K at ambient temperature
  maximum temperature: 90°C in continuous use, 450°C at peaks
• Dacron^TM Felt coated with an aluminized film
  Density of the felt: 6 kg/m
• Vacuum honeycomb common bulkhead
• Multi-Layer Insulation (MLI) placed under thermal vacuum flux: ~0.25 W/m² between 4 K and 300 K, for 40 layers of MLI

• Launcher tanks
• Superfluid helium tank
• Flight cryogenic transfer lines
• Testing Area / Material Tests

• Different Ariane Programs