MRBM (membrane LNG)

Membrane LNG containment is a non-self-supporting cryogenic system in which a thin metallic membrane lines and is supported by the ship’s inner hull through load-bearing insulation, holding LNG at minus 163 C and near-atmospheric pressure. The two dominant systems are GTT Mark III, with a corrugated 304L stainless primary membrane and Triplex secondary barrier, and GTT NO96, with double 0.7 mm Invar membranes over plywood-and-perlite insulation; the Korean KC-1 system uses corrugated stainless on both barriers. All require a complete secondary barrier for redundancy under the IGC Code. The membrane absorbs thermal contraction through corrugations (stainless) or low-expansion alloy (Invar).