Design of a glass composite anchor for LNG cargo containment systems

Abstract

Large cryogenic containments for a liquefied natural gas (LNG) should be joined to the inner hull of a ship with the consideration of the minimum heat inflow because the large temperature difference between the LNG cargo containment and the inner hull can induce considerable heat flux through the joined area. In this work, a glass composite anchor composed of two stainless steel caps and glass fiber composite body was developed considering the strength, thermal stress and heat loss of the anchor. The stainless steel caps were adhesively bonded to the top and bottom of the glass composite body. Then the top stainless cap was welded to the stainless steel membrane and the flange of bottom stainless steel cap was joined to the inner hull of a ship with bolts. The static, dynamic adhesive strength and impact characteristics between the stainless steel caps and glass composite body of the glass composite anchor at the cryogenic temperature were investigated with respect to the adhesive thickness. Since the welding heat through the top stainless cap might degrade the adhesive joint between the top stainless cap and the glass composite body, the welding effect on the adhesively bonded joint strength was also investigated. Finally, the optimal design for the glass composite anchor was suggested.