Abstract: As an important storage facility for liquefied natural gas, large LNG storage tank has the characteristics of complex structure, special materials, high quality requirements and great difficulty in construction and so forth. In recent years, with the continuous progress of LNG storage tank design and construction technology, China began to build large LNG low-temperature storage tanks of 270,000 cubic meters. This paper highlighted the assembly and construction method of the steel vault of large LNG storage tanksof 270,000 cubic meters, and it expounded from the aspects of vault partition mode, preparation of construction measures for prefabrication and installation, temporary storage mold and hoisting of vault sheet in the tanks. In addition, it also introduced the calculation of construction stability for the prefabrication of vault sheet, temporary storage, and tank hoisting after increasing the size of the tank steel vaults in the hope of providing reference for the assembly of similar tank steel vaults.

Key words: low temperature storage tank, steel vault assembly, lifting;stability analysis