Method of forming insulated angular duct sections, compatible with an automatic coil line

摘要

An angular insulated duct section and method for insulating and forming same is provided. A multi-layer composite sheet (10) is provided, including a first duct layer of sheet metal (12) having two opposed surfaces. On one of the sheet metal surfaces (12) is attached a viscoelastic foam sheet layer (14). The foam sheet layer (14) includes at least one of (A) a viscoelastic open-cell foam layer, or (B) a viscoelastic formally closed-cell foam layer in which at least a portion of closed cells therein has been opened. A substantially linear corner bend is formed in the composite sheet so as to form the angular insulated duct section with the sheet metal layer on an outside thereof and the foam sheet layer on an inside thereof. The corner bend is formed without substantial at least one of distortion or deformation of the multi-layer composite sheet adjacent the bend.