测试科学与仪器2026，Vol.17Issue(1)：72-87,16.DOI:10.62756/jmsi.1674-8042.2026006
基于脉冲涡流检测的铁磁性金属套管缺陷图像处理方法
Image processing method for defect images of ferromagnetic metal casings based on pulsed eddy current testing
摘要
Abstract
In oil and gas extraction,ferromagnetic metal casings serve as critical infrastructure to ensure the safety of hydrocarbon transport.However,under high-temperature and high-pressure conditions,casings buried deep underground are prone to deformation,twisting,and even rupture due to erosion and corrosion,potentially leading to significant economic losses and safety hazards.Therefore,regular inspection and maintenance of in-service well casings are essential.Pulsed eddy current testing(PECT)has been widely used for casing defect detection owing to its efficiency,non-contact nature,and rich information content.However,the presence of substantial noise during detection degrades the quality of defect detection images.To address this issue,we investigated image processing techniques for casing defect detection images and proposed an image processing algorithm(BIC)based on bidimensional empirical mode decomposition(BEMD),improved wavelet threshold denoising(IWTD),and contrast limited adaptive histogram equalization(CLAHE).The proposed method first applied BEMD-IWTD for noise suppression in defect detection images,followed by CLAHE for image enhancement.To validate the effectiveness of the method,defect detection experiments were conducted on casings with ring-shaped and local defects,and the acquired images were processed.After being processed with the BIC algorithm,ring-shaped defects of different depths could be effectively distinguished,especially the 1 mm and 2 mm deep defects that were previously affected by noise.In the local defect images,small-sized defects difficult to be identified due to noise interference were successfully recognized,and the defect contrast Cd was significantly improved.The results demonstrate that the proposed BIC algorithm effectively suppresses the noise in defect detection images,enhances the contrast between defects and the background,and improves defect recognition and detection accuracy,providing reliable image processing support for subsequent defect analysis.关键词
铁磁性金属套管/无损检测/脉冲涡流检测/缺陷检测/缺陷图像降噪/缺陷图像增强Key words
ferromagnetic metal casing/nondestructive testing(NDT)/pulsed eddy current testing(PECT)/defect detection/image denoising/image enhancement引用本文复制引用
邓勇,宋地霖,孙虎..基于脉冲涡流检测的铁磁性金属套管缺陷图像处理方法[J].测试科学与仪器,2026,17(1):72-87,16.基金项目
This work was supported by National Natural Science Foundation of China(No.62303385). （No.62303385）
