液化天然气储罐大角焊缝区域应力影响因素

Research on Stress Influencing Factors of Shell-to-bottom Fillet Weld Regions of Liquefied Nature Gas Cryogenic Tank

利用ANSYS对16万m3全容式液化天然气储罐金属内罐应力最大、最危险的大角焊缝区域建立参数化模型分析其安全性,通过计算得到了不同罐底边缘板厚度、边缘板外伸长度、焊缝内坡口尺寸以及内侧角焊缝焊脚长度的应力分布曲线。结果表明,在一定范围内改变以上4个尺寸,可以不同程度地改变其大角焊缝的最大应力和薄膜应力。据此给出了这4个尺寸的取值范围。

In a liquefied nature gas （LNG） cryogenic tank with a volume of 160 thousand m3 , the shell-to-bottom fillet weld is one of the biggest stress and most dangerous areas . In order to analyze the security, using ANSYS to establish the parameterized model of shell-to-bottom fillet weld, and then through calculating, the stress distribution results and stress influencing curve of twenty three kinds of models are obtained under the situation of different thickness and overhang length of annular plate, different sizes of the inner weld bead bevel and the different lengths of fillet weld. The result shows that in a certain range, changing the sizes of the above four aspects can change the biggest stress and membrane stress of shell-to-bottom fillet weld at different lev- els, and at the same time giving the recommended value ranges of the four size.