Insulated flexible duct e.g. for air conditioning systems has thermal insulation layer made from plastic forming air-filled cavities

摘要

The flexible duct (4) has an outer thermal insulating layer (6) made from plastic sheet materials (8, 12, 14) forming a series of air-filled cavities (10) or bubbles, covered by heat reflective layers (16, 18) of thin aluminum film or electrolytic coating.