碳钢件焊缝缺陷检测用正交涡流探头研究

Research on Orthogonal Eddy Current Probe for Testing Weld Flaws in Carbon Steel Plate

由于传统涡流探头具有明显的提离效应,难以检测表面不平整的焊缝。为此,基于均匀涡流检测原理,设计一种用于焊缝缺陷检测的正交涡流探头。采用理论计算方法,研究正交探头检测原理,设计探头有限元仿真模型,分析探头结构和线圈尺寸对检测灵敏度的影响。利用设计的正交涡流探头对碳钢件焊缝开展探伤检测试验。当提离量不大于2 mm时,有效检测出宽度为0.25 mm、深度为1 mm的碳钢板焊缝表面人工开口裂纹。试验结果表明,正交涡流探头能有效抑制检测过程中提离效应的影响,验证了探头用于焊缝表面缺陷检测的可行性。

Because the conventional eddy current probe has a noticeable lift⁃off effect,it is difficult to detect weld flaw with uneven surfaces.Therefore,based on the test principle of uniform eddy current,an orthogonal eddy current probe for detecting weld flaw was designed.The detection principle of orthogonal probe was studied by using the method of theoretical calculation,and the finite element simulation model of the probe was designed to analyze the in⁃fluence of probe structure and coil size on the detection sensitivity.The designed orthogonal eddy probe was used to test the weld flaw of carbon steel specimens.When the lift⁃off distance was not greater than 2 mm,the artificial open⁃ing flaws on the surface of carbon plate welds with 0.25 mm width and 1 mm depth were effectively detected.The test results showed that the orthogonal eddy current probe can effectively suppress the influence of the lift⁃off effect during the detection process,which can verify the feasibility of the probe for the detection method for weld surface flaws.