Research on Ultrasonic TOFD Imaging Inspection for Heavy-walled Weld Based on Phase Coherence Characteristics

被引：0

作者：

Chen Y. ^{[1
,2
]}

Mao Q. ^{[1
]}

Shi W. ^{[1
]}

Chen G. ^{[1
]}

Lin L. ^{[3
]}

Jin S. ^{[3
]}

Gan Y. ^{[1
]}

Wu X. ^{[1
]}

Lu C. ^{[1
]}

机构：

[1] Key Lab. of NDT, Ministry of Education, Nanchang Hangkong University, Nanchang

[2] State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing

[3] NDT & E Laboratory, Dalian University of Technology, Dalian

来源：

Jixie Gongcheng Xuebao/Journal of Mechanical Engineering | 2019年 / 55卷 / 04期

关键词：

Heavy-walled; PCI; TOFD; Ultrasonic; Weld;

D O I：

10.3901/JME.2019.04.025

中图分类号：

学科分类号：

摘要：

To improve the signal to noise ratio (SNR) and lateral resolution, phase coherence imaging (PCI) post-processing algorithm is presented and applied in ultrasonic time-of-flight diffraction (TOFD) inspection for heavy-walled welds. Firstly, delay and sum operation for the aperture data of TOFD-B image is implemented by synthetic aperture focusing technique (SAFT). Secondly, phases of aperture data were used to establish phase coherence factor which represented the phase dispersion for each pixel in the B-SAFT image. Finally, the B-SAFT image is dynamically weighted by phase coherence factor. The results show the PCI is capable of suppressing structure noise and enhancing SNR by amplifying the contribution of phase information. For austenitic weld with 78 mm thickness, the average SNR of three Φ3 side drilled hole were more than 30 dB, higher 20 dB than TOFD-B image. Furthermore, the PCI could improve the lateral resolution by enhancing aperture beam directivity. Compared to TOFD-B image, the half lateral width of defect in processed images were decreased by more than 70 percent for a 48mm thickness CV weld. © 2019 Journal of Mechanical Engineering.

引用

页码：25 / 32

页数：7

共 31 条

[1]

Shen G., Development status of nondestructive testing and evaluation technique for pressure equipment, Journal of Mechanical Engineering, 53, 12, pp. 1-12, (2017)

[2]

Gang T., Chi D., Yuan Y., Ultrasonic TOFD technique and image enhancemment based on synthetin aperture fousing techinque, Transactions of the China Welding Institution, 27, 10, pp. 7-10, (2006)

[3]

Spies M., Rieder H., Dillhofer A., Et al., Synthetic aperture focusing and time-of-flight diffraction ultrasonic imaging-past and present, Journal of Nondestructive Evaluation, 31, 4, pp. 310-323, (2012)

[4]

Xie X., Research of improving TOFD resolution based on pressure vessel welds, (2015)

[5]

Zhao X., Gang T., Xu C., Et al., Ultrasonic beam simulation and flaw signal prediction in anisotropic buttering weldment, Journal of Mechanical Engineering, 47, 8, pp. 21-27, (2011)

[6]

Nageswaran C., Carpentier C., Tse Y., Et al., Microstructural quantification, modelling and array ultrasonics to improve the inspection of austenitic welds, Insight-Non-Destructive Testing and Condition Monitoring, 51, 12, pp. 660-666, (2009)

[7]

Zhao S., Study of CCASS weld modeling and ultrasonic testing numercial simulation, (2011)

[8]

Yang L., Optimal selection ultrasonic phased array for heavy-walled CCASS pipe welds inspection, (2012)

[9]

Qu N., The study of phased array ultrasonic testing focusing characteristics on thick-wall CASS pipe, (2013)

[10]

Chen Y., Luo Z., Zhou Q., Et al., Modeling of ultrasonic propagation in heavy-walled centrifugally cast austenitic stainless steel based on EBSD analysis, Ultrasonics, 59, pp. 31-39, (2015)

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