Abstract: A clamp apparatus for holding together two abutting pipe ends, in which the pipe ends have radial flanges to facilitate the exerting of axial compressive forces on the pipe ends. The clamp includes a first strap structure and a fastening mechanism for providing circumferential compressive force on retainer segments configured to transfer the compressive force onto the flanges of the pipe ends. The clamp apparatus also includes a secondary strap structure for providing independent redundancy, relative to the primary strap, to supply back-up circumferential force onto the primary strap structure, should a failure occur in either of the fastening mechanism or the primary strap structure, to enable the clamp to maintain clamping force on the abutting pipe ends.

Abstract: A laminated duct structure for gas turbine engines, and a method for manufacturing laminated duct structures for gas turbine engines. The duct structure incorporates a metallic inner layer and a polymeric outer layer. Preferably, the thin metallic layer is a corrosion resistant material such as corrosion resistant stainless steel or titanium. The supporting outer polymeric layer is, in a preferred embodiment of the invention, a polyimide material, such as polyimide resin-impregnated fiberglass cloth.