含缺陷高压管道复合材料补强有限元模拟

Analysis Failure Mechanism of Composite Reinforced High Pressure Pipe with Outside Flaw by FEM

针对输气管道存在缺陷时容易引起气体的泄漏,利用高压管道复合材料补强力学模型,用有限元方法计算了在不同管道尺寸、厚度、缺陷面积和缺陷深度下用复合材料补强的最小层数,并绘出了补强厚度与缺陷面积和深度的关系图。计算结果表明,在极限输送气压下,缺陷深度和面积是决定补强层数的主要因素。

When the outside wall of pipe is corroded or damaged, the strength of the pipe near the flaw decrease, which would lead to gas leak when work at high pressure condition. In order to solve this problem, composite reinforced methods are often to be used to assure pipeline security. So understanding the failure mechanism is important for practical engineering use, in this paper, a FEM model was utilized to analyze the ultimate pressure when composite material applied outside the pipe, the stresses in composite material layers, the bonding layer and pipe flaw were calculated. The effects of flaw depth and size surface area were also taken into account in the calculated model. The results show that the failure of the pipe with outside reinforced composite layers most affected by the depth and size of surface area of the flaw, ie, the failure of reinforced pipeline still controlled by the flaws, but application of reinforced composite layers can prevent the further damage of the flaw and the leak of the gas.