Cryogenic strength of adhesive bridge joints for thermal insulation sandwich constructions

Abstract

Cryogenic containment systems for LH2 (Liquid Hydrogen) and LNG (Liquefied Natural Gas) generally require two barriers: the primary barrier made of stainless steel or Invar which contacts directly the cryogenic liquids, the secondary barrier made of composite or metal foil which functions as the faces of sandwich constructions for thermal insulation.

The faces of sandwich constructions are bridged with metal strips which are usually adhesively bonded for gas tightness. When cryogenic liquids are loaded in the containment system, the adhesive bridge joints are subjected to both the thermal load and deformation due to the shrinkage of the sandwich constructions.

Since the maximum deformation in the sandwich construction systems may occur in the metal bridge between the two sandwich constructions, the cryogenic performances of adhesive bridge joint with level difference, which would be generated due to manufacturing tolerance, were evaluated using both the new appropriate test method and FE analysis.