Composite insulation structure for the insulation of the interior surface of annular ducts

摘要

A flexible, composite duct insulation structure includes a first layer (12) forming an insulation layer, and a second layer (14) forming a structural support layer. The first layer (12) is adhered to the second layer (14) by an adhesive (16). The composite duct insulation structure has sufficient strength and radially outward-directed spring force of the structure alone so as to press and hold the insulation structure against the interior wall of a tubular duct (18) without additional spring structure or retaining structure.