油气管道复杂腐蚀缺陷失效压力非线性有限元研究

发布时间：2018-06-21 18:53

本文选题：压力管道 + 有限元　；参考：《西安石油大学》2015年硕士论文

【摘要】：压力管道广泛应用于工业生产和人民生活当中,管道的安全与否关乎国计民生。随着油气管道使用年限的增加,管道腐蚀现象日益严重,造成壁厚减薄,管道承压能力下降,甚至会导致管体局部腐蚀穿孔、泄漏或破裂事故的发生。实际管道的腐蚀缺陷的分布往往是随机的。因此,为了确保管道的安全运行,需要对腐蚀管道的剩余强度进行评估,研究影响相邻腐蚀缺陷管道失效压力的相关参数,分析相邻腐蚀缺陷的相互作用及影响因素等问题,为压力管道的安全性评价提供参考依据。本文通过对比真实腐蚀管道爆破实验结果与文献计算结果,验证了相邻腐蚀缺陷管道有限元模型的准确性。对腐蚀管道上的相邻腐蚀缺陷开展非线性有限元分析,研究了腐蚀缺陷间距、腐蚀缺陷深度以及腐蚀缺陷长度对相互作用和管道失效压力的影响,同时确定出了一套可行的相互作用判定准则,并提出和验证了新的极限作用距离。研究表明:轴向相邻腐蚀缺陷腐蚀缺陷长度和腐蚀缺陷深度是影响轴向极限距离的重要因素;环向相邻腐蚀缺陷间也存在极限作用距离,即环向间距以角度表示且当夹角大于20o时不发生相互作用,腐蚀缺陷深度对环向极限作用距离影响不大。对于复杂腐蚀缺陷,深、浅缺陷的深度比和长度比是影响管道失效压力的两个主要因素,而深、浅缺陷宽度比对失效压力的影响不大。
[Abstract]:Pressure pipeline is widely used in industrial production and people's life. The safety of pipeline is related to national economy and people's livelihood. With the increase of the service life of oil and gas pipeline, the corrosion of pipeline becomes more and more serious, which results in the thinning of the wall thickness, the decrease of the pressure bearing capacity of the pipeline, and even the local corrosion and perforation of the pipe body, the occurrence of leakage or rupture accident. The distribution of corrosion defects in actual pipelines is often random. Therefore, in order to ensure the safe operation of the pipeline, it is necessary to evaluate the residual strength of the corroded pipeline, study the relevant parameters that affect the failure pressure of the pipeline with adjacent corrosion defects, analyze the interaction of adjacent corrosion defects and the influencing factors, etc. It provides reference for safety evaluation of pressure pipeline. In this paper, the accuracy of the finite element model of the adjacent corroded pipeline is verified by comparing the actual experimental results of corrosion pipeline blasting with the results of literature calculation. The nonlinear finite element analysis of the adjacent corrosion defects in the corroded pipeline is carried out. The effects of the distance between the corrosion defects, the depth of the corrosion defects and the length of the corrosion defects on the interaction and the failure pressure of the pipeline are studied. At the same time, a set of feasible interaction criterion is determined, and a new limit action distance is proposed and verified. The results show that the length and depth of the axial adjacent corrosion defects are the important factors affecting the axial limit distance, and the limit action distance also exists between the circumferential adjacent corrosion defects. That is, the circumferential distance is expressed as an angle and no interaction occurs when the angle is greater than 20o, and the depth of corrosion defect has little effect on the circumferential limit action distance. For complex corrosion defects, the depth ratio and length ratio of deep and shallow defects are two main factors that affect the failure pressure of pipeline, while the ratio of depth to width of shallow defects has little effect on the failure pressure.
【学位授予单位】：西安石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE988.2

【参考文献】