In the world, there are mainly api gravity standard API650, Japanese industrial standard JIS B850 1, British industrial standard BS2654 and Chinese national standard GB5034 1. The formulas used in each code are derived from the circumferential stress calculation formula in the thin film theory, and combined with the mechanical characteristics of the oil tank, together with the allowable stress, weld coefficient and additional amount of wall thickness, they become a complete wall thickness calculation formula. The allowable stress and welding coefficient of each specification are determined according to the material performance characteristics and construction technology level of their respective countries. Therefore, according to different specifications, the calculation results of tank wall thickness with the same volume sometimes vary greatly. China's national standard GB5034 1-2003 stipulates the allowable stress and weld coefficient according to the performance characteristics of domestic materials and the overall level of domestic construction enterprises, which is more in line with the national conditions. This specification is basically adopted in the design of oil tanks in China.

Construction method: The inverted chain method is basically used in the construction of ordinary vertical storage tanks: construction preparation → material inspection → blanking → processing → inspection → welding of middle plate at the bottom of the tank → setting of middle column and umbrella frame at the bottom of the tank → assembling welding of top ring → assembling welding of side angle steel → assembling of temporary vault support → hoisting device of guide chain → assembling welding of vault → assembling welding of lower ring → hoisting of top ring wall plate → girth welding → welding of all girth joints. Prefabrication of tank body: 3 arc templates: 1 template for checking curvature of vault, with chord length not less than 2m; Check the corner deformation of the vertical weld of the internal arc formwork in 1 block, and its chord length shall not be less than1m; Check the vertical weld deformation of an outer arc template, and its chord length is not less than1m.

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