小管径弯管不饱和漏磁场模拟及缺陷量化研究OA

When passing through the small diameter elbow pipe,the leakage magnetic detector chan-ges the lift-off value and then the applicability of the traditional quantization method has to be investi-gated.This paper established a three-dimensional finite element simulation model of defective leakage magnetic field of elbow pipe,to study the influence of defect size,defect location,pipe curvature radi-us and other factors on the magnetic flux density of defects in small diameter elbow pipe,to build the quantitative model of defects in small diameter elbow pipe.The results indicate that there is a difference in magnetization intensity between straight pipe and elbow pipe,and uneven magnetic field occurs in the elbow pipe;the defect size is the main factor affecting the magnetic flux density,and the magnetic flux density of the inner arch of the elbow pipe is larger than that of the outer arch under the same de-fect size;the curvature radius of the pipeline changes the distribution of the magnetic flux density of the pipeline,and an unsaturated leakage magnetic field is formed.This research builds a small pipe di-ameter elbow defect quantification model for small pipe diameter elbow defect length,width and depth of the quantification error of 7.10%,9.77%,and 8.74%,respectively.