Abstract: A ship comprises: a liquefied gas storage tank; a multi-stage compressor for compressing a boil-off gas discharged from a storage tank and comprising a plurality of compression cylinders; a second heat exchanger for heat exchanging a fluid, which has been compressed by the multi-stage compressor, and thus cooling same; a first decompressing device for expanding a flow (“flow a1”) partially branched from the flow (“flow a”) that has been cooled by the second heat exchanger; a third heat exchanger for heat exchanging, by “flow a1” which has been expanded by the first decompressing device as a refrigerant, the remaining flow (“flow a2”) of “flow a” after excluding “flow a1” that has been branched and thus cooling same; and a second decompressing device for expanding “flow a2” which has been cooled by the third heat exchanger.

Abstract: Disclosed is a re-liquefying device using a boil-off gas as a cooling fluid so as to reliquefy the boil-off gas generated from a liquefied gas storage tank provided in a ship. A boil-off gas re-liquefying device for a ship comprises: a multi-stage compression unit for compressing boil-off gas generated from a liquefied gas storage tank; a heat exchanger in which the boil-off gas generated from the storage tank and the boil-off gas compressed exchange heat; a vaporizer for heat exchanging the boil-off gas cooled by the heat exchanger and a separate liquefied gas supplied to a fuel demand source of a ship, and thus cooling the boil-off gas; an intermediate cooler for cooling the boil-off gas that has been cooled by the heat exchanger; and an expansion means for branching a part of the boil-off gas, which is supplied to the intermediate cooler, and expanding the same.

Abstract: A heat insulation structure for corner parts of a liquefied natural gas (LNG) storage tank includes a secondary insulation wall arranged on an inner wall of a hull, a secondary sealing wall disposed on the secondary insulation wall, a primary insulation wall arranged on the secondary sealing wall, and a primary sealing wall disposed on the primary insulation wall. The heat insulation structure includes a corner assembly finishing an edge of the primary sealing wall at a corner part of the storage tank to complete sealing of the storage tank. The corner assembly includes an endcap sheet finishing each of four corners of the primary sealing wall provided to each surface of the storage tank to seal the four corners. The endcap sheet includes an endcap corrugation and an elongated corrugation extending in a direction perpendicular to a direction in which the endcap corrugation extends.

Abstract: An insulating wall fixing device for liquefied natural gas storage tanks includes: a base socket; and a securing stud inserted into the base socket. The base socket is formed on an upper surface thereof with an insertion hole through which the securing stud is inserted into the base socket and has an interior space in which one end of the securing stud is settled. The securing stud includes an insertion portion inserted into the interior space of the base socket through the insertion hole and a fastening portion protruding from the insertion portion outwardly of the base socket. The insertion portion includes a spherical shape and multiple leg members divided by a groove formed from one end of the insertion portion to the other end of the insertion portion. The multiple leg members of the insertion portion are retracted toward the groove.