漏磁检测多排传感器的数据修正理论及方法

漏磁检测因其显著的技术优势,被广泛应用于无损检测铁磁性构件中的缺陷,尤其是在油气管道的内检测领域。 漏磁 检测信号的空间分辨率由传感器的排布密度决定,但传感器的排布密度受其尺寸限制,尤其是对单排传感器。 因此为提升检测 信号的空间分辨率,传感器的多排、错排布置是简单易行的方法。 由于多排传感器所处位置的背景磁场不同,不同背景磁场对 检测信号的影响规律尚不清晰,因此需要对以上问题进行理论分析,并提出对多排传感器检测数据进行修正的方法。 本研究基 于磁荷理论,将缺陷检测信号划分成背景磁场和缺陷漏磁场两部分的叠加,给出了两者叠加的规律。 基于此提出了对多排传感 器的检测数据进行修正的方法,并通过 COMSOL 仿真和实验结果验证了所提方法的有效性。

Theory and method of data correction for multi-row sensors in MFL detection

Due to the remarkable technical advantages, magnetic flux leakage testing (MFL) is widely used in nondestructive testing of ferromagnetic components, especially in the field of internal inspection of oil and gas pipelines. The spatial resolution of MFL inspection is determined by the sensor arrangement density. However, the sensor arrangement density is limited by its size, especially for single-row sensors. Therefore, to improve the spatial resolution for the inspection, the multi-row and staggered arrangement of sensors is a simple and feasible method. Due to the different background magnetic fields at the positions of multiple rows of sensors, the influence law of different background magnetic fields on the detection signal is not clear. Therefore, it is necessary to carry out a theoretical analysis of the above problems. A method is proposed to correct the detection data of multiple rows of sensors. Based on the magnetic charge theory, the defect detection signal is divided into the superposition of the background magnetic field and the defect leakage magnetic field, and the superposition rule of the two is given. Based on this, the method of correcting the detection data of multiple rows of sensors is proposed. The effectiveness of the proposed method is evaluated by COMSOL simulation and experimental results.