High efficiency loose multi-foil thermal insulation structure with

Abstract

A loosely wrapped multi-layer thermal insulation structure is provided by coextensively winding, a continuous thin metal foil and a superimposed continuous low thermal conductivity porous material spacer about a mandrel, preferably functioning as an inner metallic shell for such loosely wound metal foil and spacer assembly. A plurality of narrow low thermal conductivity porous material strips are interposed between adjacent turns of the spiral wound metal foil and spacer assembly at laterally spaced positions throughout the assembly to form localized, narrow dense wound material areas defining an integral load-bearing system for the thermal insulation structure. Longitudinally extending permanent getter material strips may be bonded to the outer peripheral surface of the inner metallic shell defining gas passages for gas diffusion within the metal foil and spacer assembly. The metal foil may be perforated to facilitate that action.