Air Duct

Trocellen PE foam air ducts

The production of air ducts in a twinsheet thermoforming process using cross-linked PE foam was invented by Trocellen and has proven itself as technically and commercially attractive alternative to the traditional air ducts made by extrusion blow-moulding of polypropylene (PP).

Trocellen’s distinguished knowhow and in-depth customer support regarding optimal material choice and process parameters in combination with the company’s perfectly suited chemically cross-linked PE foams have made Trocellen the preferred partner for manufacturers of serial twinsheet air ducts as well as car manufacturers.

The PE foam can be thermoformed into complex geometries and air ducts for diverse application areas within the vehicle such as instrument panel, pillars, floor and roof can be realised. The possibility to include reinforcement ribs, different fixation methods and other individual solutions allow the construction of air ducts meeting high demands.

Trocellen PE foam air ducts


Due to the properties of the closed-cell PE foam the air ducts show excellent advantages compared to rigid plastic ducts:

• Weight reduction – up to 65 % lighter than solid air ducts
• Thermal insulation improvement – reduction of energy loss
• Acoustic absorption – up to 5 dB less airflow noise
• Sealing function – no squeak & rattle
• No condensation – no bacteria
• Odourless material – no smell, no fogging
• Easy production process – thermoforming and cutting
• Easy assembly – high flexibility, good restoring behaviour
• Easy prototyping – cost-efficient prototype tools and fast prototype production

Comparison Matrix – soft PE foam vs. rigid PP air ducts

Parameter Thermoformed soft, felxible duct Extrusion blowmoulded rigid, stiff duct
Material XLPE foam 1) PP solid
Weight reduction up to 65 % lighter – (compact material)
Thermal insulation +
less energy loss:
efficient use of AC,
Sound damping +
better noise absorption,
less ventilation noise
Assembly / Installation +
easy (felxible),
good sealing function

difficult (stiff), additional sealings required
Squeak & Rattle +
squek & rattle minimised
even in tight spaces
Heat resistance (° C) -30/+105 -30/+120
Fogging + +
Burning rate (FMVSS 302) < 100 mm/min < 100 mm/min
Recycling + +