Real-Time Determination and Evaluation Method of Cracks by Using ACFM Technique
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摘要: 交流电磁场检测(ACFM)技术已经广泛用于海洋各类结构物的缺陷检测和评估中。传统的基于特征信号或蝶形图的缺陷判别方法易引起误判且难以实现实时判定与评估。搭建ACFM阵列检测系统,利用Bx能量谱和Bz相位导数阈值算法实时判定裂纹,依据阈值参数对裂纹危险等级进行评估,并开展裂纹检测与评估试验。结果表明:交流电磁场特征信号Bx能量谱可作为裂纹长度评估阈值,特征信号Bz相位在裂纹区域发生明显的翻转;基于能量谱和相位导数阈值的判定方法能够实时判定裂纹;利用阈值参数可对裂纹危险等级进行评估;基于能量谱和相位导数阈值的ACFM检测系统能够实现裂纹的实时定量与定位评估。Abstract: Alternating current field measurement (ACFM) technology has been widely used in ocean engineering for detection and evaluation of cracks on structures. Conventional testing method is easy to introduce miscalculation and is hardly to achieve real-time determination and evaluation of cracks based on characteristic signals or butterfly-plot using ACFM probe. A new judgment method is presented based on ACFM system with sensor array. The energy spectrum of Bx and the derivative of Bz phase are combined together as threshold to judge cracks in real-time. The dangerous grade of cracks is evaluated based on the threshold. The crack test and evaluation experiments are carried out. The results show that the energy spectrum of Bx can be set as the threshold of crack length. The Bz phase reverses greatly when the crack is present. The cracks can be confirmed by the threshold real-time determination method. The dangerous grade of cracks can be evaluated using the threshold parameters. The cracks can be evaluated and located by the ACFM testing system based on the energy spectrum and phase derivative threshold.
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Keywords:
- ACFM /
- energy spectrum /
- phase /
- threshold /
- real-time determination and evaluation
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[1] 李伟,袁新安, 陈国明, 等. 基于外穿式交流电磁场检测的钻杆轴向裂纹在役检测技术研究[J]. 机械工程学报, 2015, 51(12):8-15. [2] YUAN X A, LI W, CHEN G M, et al. Two-step interpolation algorithm for measurement of longitudinal cracks on pipe strings using circumferential current field testing system[J]. IEEE Transactions on Industrial Informatics, 2018, 14:394-402.
[3] 冷建成,田洪旭,周国强,等. 自升式海洋平台关键部位MMM与ACFM联合检测[J]. 海洋工程, 2017, 35(2):34-38. [4] LI W, CHEN G M, ZHANG C R, et al. Simulation analysis and experimental study of defect detection underwater by ACFM probe[J]. China Ocean Eng., 2013, 27(2):277-282.
[5] LI W, YUAN X A, CHEN G M, et al. A feed-through ACFM probe with sensor array for pipe string cracks inspection[J]. NDT&E International, 2014, 67:17-23.
[6] LUGG M C. The first 20 years of the A.C. field measurement technique[C]//Proceedings of the 18th World Conference on Non-destructive Testing. Durban:[s.n.],2012:16-20.
[7] NOROOZI A, HASANZADEH R P R, RAVAN M. A fuzzy learning approach for identification of arbitrary crack profiles using ACFM technique[J]. IEEE Transactions on Magnetics, 2013, 49(9):5016-5027.
[8] TOPP D. Recent developments and applications of the ACFM inspection method and ACSM stress measurement method[J]. Nondestructive Testing Australia, 2005, 42(5):143.
[9] NICHOLSON G L, KOSTRYZHEV A G, HAO X J, et al. Modelling and experimental measurements of idealised and light-moderate RCF cracks in rails using an ACFM sensor[J]. NDT&E International, 2011, 44:427-437.
[10] 李文艳, 李伟, 陈国明. 交变磁场测量系统的设计及其微弱信号的检测方法[J]. 无损检测, 2010, 32(12):977-979. [11] 刘珊, 张荣华, 张牧, 等. 基于Bz (Pmax)相轨迹的电磁涡流无损检测方法[J]. 仪器仪表学报, 2015, 36(11):2458-2465. [12] 安周鹏, 肖志怀, 陈宇凡,等. 小波包能量谱和功率谱分析在水电机组故障诊断中的应用[J]. 水力发电学报, 2015, 33(6):182-190. [13] 朱红运, 王长龙, 王建斌, 等. 圆盘状脉冲涡流差分传感器缺陷检测信号的解析计算[J]. 仪器仪表学报, 2015, 36(8):1707-1714. [14] 罗清旺, 师奕兵, 王志刚, 等. 一种基于远场涡流的管道大面积缺陷定位检测方法[J]. 仪器仪表学报, 2015, 36(12):2790-2797. [15] LI W, YUAN X A, CHEN G M, et al. High sensitivity rotating alternating current field measurement for arbitrary-angle underwater cracks[J]. NDT&E International, 2016, 76:123-131.
[16] LI W, YUAN X A, CHEN G M, et al. Induced circumferential current for transverse crack detection on a pipe string[J]. Insight, 57(9):528-533.
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