管道横向励磁漏磁内检测器研制

1. 中油管道检测技术有限责任公司;2. 大庆油田有限责任公司天然气分公司

油气管道;缺陷;横向;轴向;励磁;检测

Development of transverse excitation MFL inline detector
YU Chao1, ZHANG Yongjiang1, LI Yanchun1, ZANG Yanxu1, WANG Jinxing2, LIN Chuanbo2, REN Huan2

1. China Petroleum Pipeline Inspection Technologies Co. Ltd.; 2. Daqing Oilfield Limited Company Natural Gas Company

oil and gas pipeline, defect, transverse, axial, excitation, inspection

备注

针对长输油气管道轴向金属损失缺陷检测的问题,研制了一种适用于管径711 mm 的横向励磁漏磁内检测器。横向励磁漏磁检测器由驱动节与记录节连接而成,其结构主要包括支撑系统、驱动系统、磁化系统、传感器系统、采集系统等。通过采用辅助磁极的励磁设计,横向励磁漏磁内检测器磁化系统不但能够达到管道壁厚的磁化饱和要求,而且改善了磁化效果,使传感器位置处的漏磁场梯度减小,提高了缺陷量化精度。将新研制的管道横向励磁漏磁内检测器进行牵拉试验和工业应用验证,结果表明:与轴向励磁漏磁内检测器相比,管道横向励磁漏磁内检测器采集的轴向沟纹、轴向类裂纹缺陷的数据信号更明显,可提高轴向缺陷的检测精度与检出率,对于识别管道轴向缺陷具有重要的工程意义。(图6表4,参[14]

A transverse excitation magnetic flux leakage (MFL) inline detector, with a diameter of 711 mm, was developed in response to the difficulty in detecting axial metal loss defects of long-distance oil and gas pipelines. Linked by the driver and the recorder, the transverse excitation MFL inline detector is mainly composed of a support system, a drive system, a magnetization system, a sensor system, and an acquisition system, etc. With excitation design of auxiliary magnetic poles, the magnetization system of the transverse excitation MFL inline detector can, in addition to meeting the magnetization saturation requirement of the pipeline wall thickness, improve the magnetization effect, reduce the MFL field gradient at the sensor position, and enhance the quantification accuracy for defects. Traction test and industrial application verification were conducted on a new pipeline transverse excitation MFL inline detector, and the results indicate that, the data signals of axial grooves and axial cracklike defects, which are acquired by the transverse excitation MFL inline detector, are clearer compared with the axial excitation MFL detector. This may inevitably contribute to the improved detection accuracy and detection rate of axial defects, as well as the great engineering significance for detecting and identifying axial pipeline defects. (6 Figures, 4 Tables, 14 References)