Influences of weld reinforcement and defect on magnetic flux leakage testing of pipeline girth weld
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摘要: 基于轴向漏磁检测技术，采用有限元方法结合牵拉试验对管道环焊缝的漏磁场进行分析。通过改变焊缝余高以及焊缝中心处椭球型凹坑缺陷的尺寸，得到了描述漏磁场特征的磁通密度分布曲线。结果表明，焊缝中心无缺陷时，漏磁信号呈典型的增厚型特征，且随余高增加，磁通密度径向分量峰峰值、轴向分量峰谷值均非线性增大；焊缝中心存在椭球型凹坑时，漏磁信号出现复合现象，即表现为外侧焊缝的增厚型与中心缺陷的减薄型漏磁信号的叠加，且随余高增加，焊缝处缺陷的减薄型信号特征减弱。相同缺陷在管壁、熔合区、焊缝中心处的漏磁信号依次减弱，说明同样缺陷在焊缝中心时最不易被检出，该结果与牵拉试验结果一致。Abstract: The magnetic flux leakage (MFL) characteristics of pipeline girth weld were analyzed using finite element method combined with the pull test based on axial magnetic flux leakage principle. By changing weld reinforcement and the size of ellipsoid defect in the center of weld, the magnetic flux density distribution curves were obtained. The results show that the magnetic field distribution of pipeline girth weld appears thickening-type characteristic when there is no defect in the weld center. The radial component peak-to-peak value and the axial component peak-to-valley value of magnetic flux density increase non-linearly. Magnetic flux leakage signals show the magnetic field distribution characteristics of the weld and the ellipsoid defect, that is, the superposition of the thickening by weld and the thinning by defect. Moreover, with the increase of weld reinforcements, the thinning type signal characteristics of the weld defect become weaker. The intensity of magnetic flux leakage signal for the same size defect follows the sequence as from strong to week:pipe wall, fusion zone and weld, indicating that the same defect is most likely to be detected in the weld center, which is consistent with the result of the pull test.
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[1] 王婷,杨辉,冯庆善,等. 油气管道环焊缝缺陷内检测技术现状与展望[J]. 油气储运, 2015, 34(7):694-698. [2] 胡朋, 陈金忠, 康小伟,等. 长输油气管道内检测数据的比对[J]. 无损检测, 2021, 43(7):90-94. [3] 戴光, 吴忠义, 朱祥军,等. 管道内外壁缺陷的漏磁检测[J]. 无损检测, 2018, 40(3):19-23,28. [4] 于永亮, 业成, 杨志军,等. 管道补板漏磁检测信号的研究[J]. 无损检测, 2021, 43(8):31-35. [5] 胡丹, 高向东, 张南峰,等. 焊缝缺陷检测现状与展望综述[J]. 机电工程, 2020, 37(7):736-742. [6] CHEEPU M, VENKATESWARLU D, RAO P N, et al. Effect of process parameters and heat input on weld bead geometry of laser welded titanium Ti-6Al-4V alloy[J]. Materials Science Forum, 2019, 4783.
[7] 高松巍, 郑树林, 杨理践. 长输管道漏磁内检测缺陷识别方法[J]. 无损检测, 2013, 35(1):38-41. [8] 毛瑞麒, 马梦想, 饶连涛,等. 管道环焊缝缺陷漏磁检测仿真模拟[J]. 电焊机, 2020, 50(11):28-36. [9] 邵卫林, 陈金忠, 马义来,等. 管道盗油孔的漏磁内检测信号识别[J]. 无损检测, 2017, 39(5):6-9. [10] 苏林, 成文峰, 刘保余,等. 管道环焊缝缺陷漏磁检测信号仿真分析[J]. 焊接, 2020, (3):10-16,65. [11] 苏林, 成文峰, 许志军,等. 油气管道缺陷漏磁检测有限元模拟[J]. 焊管, 2020, 43(4):8-13,22.
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