基于金属磁记忆的管道缺口分析

Analysis of Pipe Notch Based on Metal Magnetic Memory

管道是油气开发作业和运输过程中的重要组成部分。随着油气管道的广泛使用,由缺口引起的管道结构不连续和应力集中现象需要重点关注。金属磁记忆检测是目前较为新颖的无损检测技术,可诊断和检测管道缺口。为研究缺口不同特征对磁记忆信号的影响,基于力磁耦合数值模型,采用有限元方法对X70油气管道不同缺口特征下的磁记忆信号变化进行分析。结果表明:缺口宽度及深度增加都会使磁记忆信号切向分量H(x)的最大值及法向分量H(y)极值的绝对值逐渐增大;磁记忆信号的法向分量H(y)相对于磁记忆信号的切向分量H(x)更加敏感;缺口深度改变对磁记忆信号的影响要大于缺口宽度改变对磁记忆信号的影响。

Pipelines are an important part of the oil and gas development and transportation process. With the widespread use of oil and gas pipelines, the discontinuity of pipeline structure and stress concentration caused by notch need to be paid attention.Metal magnetic memory testing is a relatively new non-destructive testing technology at present, which can diagnose and detect pipeline notch. In order to study the influence of different notch features on the magnetic memory signal, based on the force-magnetic coupling numerical model, the linear elastic finite element method was used to analyze the changes of the magnetic memory signal under different notch features of the X70 oil and gas pipeline. The result shows that the increase of the notch width and depth will gradually increase the maximum value of the tangential component of the magnetic memory signal and the absolute value of the extreme value of the normal component, and the normal component of the magnetic memory signal is more sensitive than the tangential component of the magnetic memory signal, and the influence of the change of the notch depth on the magnetic memory signal is greater than that of the change of the notch width.