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Paper Abstracts of 2008 FENDT
Source:    Publish Time: 2008-07-28 22:45   2356 Views   Size:  16px  14px  12px
The research of pusled eddy current testing technologyBinqiang Zhang1, Haitao Wang1, Guiyun Tian1,2, Wangping1(1College

The research of pusled eddy current testing technology
Binqiang Zhang1, Haitao Wang1, Guiyun Tian1,2, Wangping1
(1College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016,China
2 College of Electical, Electronic and Computer Engineering, Merz Court, University of Newcastle Upon Tyne, UK)
Abstract:The pulse eddy current testing technology is a new kind of eddy current non-destructive inspection technology. Compared with the conventional single frequency eddy current testing technology, it contains more flaw feature information in its response signal because of its wider frequency spectrum. On the basis of the experiment of inspecting the depths of defects which makes use of pulse eddy current, this paper use the method of differential coefficient to analyze the signal of pulsed eddy current. The experimental results indicate that it is possible to enhance the examination system's linearity using the differential signal after differential calculus.
Keywords:Pulse eddy current non-destructive inspection technology differential signal

The Application of Guided Ultrasonic Waves Testing Technology for Pressure Piping Inspection
Cai Guoning, Xu Wei
Jiangsu Province Special Equipment Safety Supervision Inspection Institute, Nanjing, 210003, China
Abstract: The guided ultrasonic waves testing technology is a new NDT technology, and it is widely used in inspecting of pressure pipings in recent years. Insulated pipings are mainly used for transferring oil and chemicals. In the past, the insulation of the pipings should be removed during testing, and it is costly. When the insulated pipings are tested by the guided waves, the insulation should be removed only one meter in length to fix the testing ring, and the guided waves are transmitted along the pipings, meanwhile, detecting the reflective wave which is caused by a flaw to determine the location and size of the flaw, this will be helpful in the inspection of the industrial pipings. The research on the guided wave technology is based on the scientific acoustic theory and it is also supported by a lot of tests. This paper expresses when testing insulated pipings, the mode of guided waves and the frequency based on the pipe thickness has been settled, the reflective waves will indicate the flaw location and size. This point of view has been verified through some site tests.
Keywords: Guided waves; Wave shapes; On-line testing for pipes; Verification

Optimum design and simulation study of linear phased arrays element size
CAI pengwu1 LIANG hua2 WANG haitao1 LIANG bin2
1 Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;
2 Nanjing Boiler &Pressure Vessel Supervision and Inspection Institute, Nanjing 210016, China;
Abstract: The ultrasonic phased array testing technology is a new development direction in recent industry nondestructive testing domain, thereinto, the design of the phased array transducer is the very pivotal portion. In this article, we take the function of the beam directivity as a model, analyzed the influence of the phased array element size on the beam directivity with the MATLAB programming simulation, and used a simple method to optimize the phased array element size
Keyword: linear phased arrays; beam directivity; ultrasonic NDT; Matlab simulation

Experimental investigation and application of acoustic emission on multilayer
wrapped high-pressure vessels
Chao Huaixiang, Zhu Weiguo, Song Mingda, Yuan Tao, Wang Chunmao
(Shandong Special Equipment Inspection & Research Academy, Jinan Shandong, 250013)
Abstract: Through experimental investigation and destructive comparison for three multilayer wrapped high-pressure vessels using acoustic emission method, an acoustic emission testing technology of multilayer wrapped pressure vessels is studied and the evaluation criterion of testing results is established. The method is applied to 80 urea reactors and many crack flaws are founded. These applications show that acoustic emission testing technology of multilayer wrapped urea reactors is effective.
Keywords: multilayer wrap; pressure vessel; acoustic emission; experimental investigation

Ultrasonic infrared thermography testing for the quality of laser welded seams
CHEN Da-peng, LI Xiao-li, LI Yan-hong, ZHANG Cun-lin, FENG Li-chun, Tao Ning
(Department of Physics Capital Normal University, Beijing 100037)
Abstract: The ultrasonic infrared thermography is a new nondestructive testing technology. It uses ultrasonic as heat source to heat the cracks selectively. At the same time, an infrared camera detects the surface temperature of the sample. In this paper, it gives the introduction of the principle of ultrasonic infrared thermography, two kinds of laser welded seams were tested using this method, and the effects of laser power and welding velocity on the quality of welded seams can be analyzed by the results.
Keywords: welded seams, ultrasonic excitation, infrared thermography, crack

Designed of Weld Flaw Testing Instrument
Chen Jingui
(Xiamen IDEA Electronic Technology Co.,LTD 361009)
Abstract: The new Weld Flaw Testing method based on research other methods in many years, then to bring the matrix form & Alternating MFL method, which used this method to design & make testing instrument, it is the first multi-function and small-size of portable instrument in the domestic. To introduce the hardware & software of the instrument, and how to resolve the key technical. Through the engineering experiment in actual, showing the instrument not only have operate in brief ,but also examination result accurate credibility etc.
Keywords: Nondestructive Testing Weld Flaw Magnetic Flux Leakage Magnetic Memory

The Research on the Technology of Industrial Computed Tomography Image Size Measurement
Chen Ping*, Pan Jin-Xiao, Liu Bin
National Key Laboratory for Electronic Measurement Technology, North University of China,
Taiyuan 030051, China
Abstract: As one of the useful non-destruction detection technologies, Industrial Computed Tomography (ICT) image size measurement may not only correctly detect the inner construction of workpieces without destruction, but also may be considered as the basic of quality detection and reverse design. In the view of some advantages and disadvantages about some conventional methods, in this paper, in order to improve the precision of image size measurement, a new arithmetic of size measurement is presented by constructing the approximate function of edge degradation. First this arithmetic constructs the approximate function of edge degradation and confirms the optimal point of edge detection, according to the information of image intensity and inflexions. Then in order to accurately extract the information of image edge, this constructed function is used to revise the primary image; hence the measurement of CT image is accomplished.
Excellent results are obtained on the simulations and experiments. This new arithmetic can effectively extract the information of CT image edge,and get an accurate measurement result.
Keywords: Industrial Computed Tomography; Size Measurement; Edge Extraction; Approximate Function; Inflexion

Comparison between TOFD and Conventional NDT Methods
Chen Yubao
(Guangdong Special Equipment Inspection Institute Guangzhou 510655)
Abstract: TOFD technique is based on measurement of the time-of-flight of the ultrasonic waves diffracted from the top and bottom tips of a defect or discontinuity when a longitudinal wave is incident on it. Compared with radiography testing (RT) and manual ultrasonic testing technique (UT), the TOFD technique, which is based on diffraction, is more precise to sizing height and more reliable to inspection of the defects. So, the detectable reliability of the discontinuity is much enhanced than the traditional NDT methods. This paper emphatically describes the inspection of butt weld on steel specimen using TOFD technique in our laboratory, compares the testing results among TOFD, RT and manual UT. Finally, the comparing conclusion is given.
Keywords: TOFD, RT, UT, Welded Specimen

Studies on the Numerical Simulation Method for Electromagnetic Acoustic Technique
Cuixiang Pei, Zhenmao Chen
(MOE Key Laboratory for Strength and Vibration, School of Aerospace,
Xi'an Jiaotong University, Xi'an, 710049, China)
Abstract: As no physical contact is necessary between the transducer and test-piece, the electromagnetic acoustic technique (EMAT) can not only improve the inspection efficiency but also can extend the application area of ultrasonic NDT to the fields of a high temperature, a high speed and on-line inspection. Recently, EMAT has become a hot topic in the researches on ultrasonic NDT. In this paper, a finite element method for the numerical simulation of electromagnetic ultrasonic testing signals is established and the corresponding numerical code is developed. In order to prove the validity of the code, propagation behaviors of ultrasonic waves excited by transducers of different structure are investigated by using the developed code. The simulation method and code provide a useful tool for the defect sizing and transducer optimization in practical application of EMAT.
Keywords: Electromagnetic Acoustic Testing; NDT; Finite Element Method; Numerical Simulation

Special strain gage used for special equipment inspection
David Hu,Calvin LIU
Shanghai Sumfar Technology Co., Ltd.
Abstract: The technology and application of some special strain gages made in Japan were introduced in this paper. Particularly the application on Special Equipments Inspection was focused in this paper. More selection for strain measurement is provided to inspection engineers.
Keywords: Strain gage, waterproof, high temperature, low temperature

Characterization of stress concentration of ferromagnetic materials by means of metal magnetic memory testing
Dong Lihong1, 2, Xu Binshi1, Dong Shiyun1, Lu Xu2, Chen Qunzhi3, Wang Dan1
1. National Key Laboratory for Remanufacturing, Beijing 100072 China;
2. Foundation Department, Mechanical Engineering College, Shijiazhuang 050003 China;
3. Beijing Aeronautical Technology Research Center, Beijing 100076 China;
Abstract: In order to study the coupling relationship between degree of stress concentration and Hp(y) signal of metal magnetic memory, tension-tension fatigue test of sheet specimens with precut notches of different stress concentration factor were preformed. During the testing process Hp(y) signals from three measured lines on the typical positions of specimen surface were collected. The results indicated that the Hp(y) signal curves of the measured lines on the central position without precut notch exhibited good linearity, while magnetic curves of the measured lines near the precut notch or across the notch showed a feature of magnetic abnormal peak. Moreover, the magnetic gradient K of abnormal magnetic peak increased with the stress concentration factor increasing, which could be potentially used to characterize the degree of stress concentration of ferromagnetic materials.
Keywords: ferromagnetic material; metal magnetic memory; stress concentration; magnetic abnormal peak

Automatic Weld Defect Detection in Real-time X-ray Images Based on D-S Evidence Theory
Du Dong, Hou Runshi, Shao Jiaxin, Wang Li, Chang Baohua
Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, P.R.China
Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
Abstract: Automatic weld defect inspection in real-time X-ray image has the advantages of objective, normative and efficient. But real-time X-ray image usual has low signal-to-noise ratio, and most of the existing automatic inspection systems only use single defect segment method, which lead to the outstanding conflict between false alarm and missed detection. In this paper, the redundancy and complementarity are analyzed in two defect segmentation methods of weld X-ray image, i.e., background subtraction and gray-level wave analysis. Then, the information fusion method of them is proposed based on D-S evidence theory. Results show that the false alarm and missed detection are decreased effectively by the information fusion method.
Keywords: Real-time X-ray image, automatic inspection of weld defects, information fusion, D-S evidence theory

Research on the Metal Magnetic Memory Testing Based on Wavelet Packet energy spectrum
FAN Zhen-zhong, REN Ji-lin, BAI Lu
Nanchang HangKong University,the Key Laboratory of Nondestructive Testing, Ministry of Education,Nanchang Jiangxi 330063
Abstract: The wavelet packet energy spectrum analysis method of magnetic memory signals is proposed in this paper. On the theoretical basis of wavelet packet transform, by carrying out stretching experiments on specimens of 45# steel and aeronautical ferromagnetic material 18CrNi4A, magnetic memory signals under different loads on the surface of the specimens can be acquired and analysed with wavelet packet energy spectrum. Thus the stress concentration part and its degree of the specimens can be judged.
Keywords: non-destructive test,metal magnetic memory; wavelet packet; energy spectrum

Method of valve leakage inspection online based on acoustic emission technology
FANG Xue-feng,LIANG Hua,XIA Zhi-min,ZHU Yu-ming
(Nanjing institute of boiler and pressure vessel supervision and inspection, Nanjing 210002, China)
Abstract: The principle、merits and system of valve inspection online by acoustic emission technology were described. The common inspection points and typical wave signal were presented. Application value was discussed at last.
Keywords: acoustic emission technology, valve, inspection, leakage, stress concentration

AE Monitoring During Aircraft Flight Loading Conditions Fatigue Test
FENG JianFei1, WU GuanHua1, GENG RongSheng2, WU Wei1
(1. Nanchang Hangkong Universty,Nanchang,330063;
2. Beijing Aeronautical Technology Research Center, Beijing,100076)
Abstract: The technology of acoustic emission (AE) real time monitoring the critical structures (include un-approachability components) during aircraft flight loading conditions fatigue test(FLCFT) was introduced. In a noise background due to severe shock and vibration, first of all, we seek many AE signal process modes what were time-based, amplitude-based, energy-based and spatial filtering techniques. After acquire the pre-process AE signal, we adopt a new AE signal analysis principle: give priority to AE diagnostic parameter trend analysis , multi-parameter analysis identifications and look others (include waveform analysis)as assistant method. Real time monitoring of these critical structures was realized, and successful to predict a crack germination that come from a interlayer of a bolt hole. The mean of AE monitoring played a key role for the fulfillment of the FLCFT.
Keywords: aircraft, acoustic emission (AE), Flight load, Fatigue Test, trend analysis

Nondestructive Testing Technique for Atmospheric Storage Tanks
Fujun Liu, Shoubao Ding, Yanting Xu, Xiaolian Guo
(Zhejiang Provincial Special Equipment Inspection and Research Institute, Hangzhou, P. R. China)
Corresponding author, Phone: +86-571-860-26-412; Fax: +86-571-860-26-412; E-mail:
Abstract: In china, atmospheric storage tanks are not included in the management of special equipment, and therefore they are not required to be inspected compulsorily. There is larger difference between China and developed countries on atmospheric storage tank inspection technique than the other techniques on the inspection of pressure vessels. It is widely believed that the strength worsening and perforation of the tank is mainly caused by the serious corrosion at the bottom surface of tank floor. The present development of nondestructive testing on atmospheric storage tank was analyzed systematically in this paper, in which the principle, standard present status, the usage of inspection equipments and the application of the acoustic emission testing and magnetic flux leakage testing techniques on atmospheric storage tanks were mainly introduced. The problems existing in the inspection equipments usage were discussed. A practice for inspecting and evaluating atmosphere storage tanks using these testing methods was proposed.
Keywords: atmospheric storage tank; acoustic emission testing; magnetic flux leakage testing; leakage

G. Vértesy1, I. Tomáš2, S. Kobayashi3
1Research Institute for Technical Physics and Materials Science, Hungarian Academy of Sciences H-1525 Budapest, P.O.B. 49, Hungary
2Institute of Physics, Academy of Sciences of the Czech Republic
Na Slovance 2, 18221 Praha, Czech Republic
3Non Destructive Evaluation and Science Research Center, Faculty of Engineering
Iwate University, 4-3-5 Ueda, Morioka 020-8551, Japan
Abstract: Three series of low carbon steel samples, plastically deformed by cold rolling to five consecutive stages of deformation, were investigated by the method of Magnetic Adaptive Testing, typical by its low required magnetization of the samples. Samples in one series were magnetically closed, those in the other two series were magnetically open. Results of the non-destructive magnetic tests were compared with the destructive mechanical measurements of Vickers hardness and ductile-brittle transition temperature. Linear, sensitive correlation with low scatter of values was found between the magnetic parameters and the two mechanical ones for any shape of the investigated specimens. Based on these results, Magnetic Adaptive Testing is suggested as a highly promising non-destructive alternative of destructive Charpy impact tests for monitoring irradiation embrittlement of surveillance samples in pressure vessels of nuclear reactors.
Keywords: Nondestructive material evaluation, Magnetic hysteresis measurements, Magnetic Adaptive Testing, Steel degradation

Thermal-wave fields of bi-layered spherical solids in laser induced photothermal technique
Guangxi Xie1, 2, Zhifeng Chen1, and Chinhua Wang1*
1 Key Lab of Modern Optical Technologies of Jiangsu Province, Institute of Modern Optical Technologies, Suzhou University, Suzhou, Jiangsu, 215006
2Department of Physics, Jiangnan University, Wuxi, Jiangsu, 214122, P. R. China
Abstract: We present a theoretical model for evaluating solid bi-layered spherical samples (surfaces) which are heated by a frequency modulated light beam in support of thermal-wave diagnostics by means of laser infrared photothermal radiometry PTR. Based on the Green function method, the specific Green function corresponding to the composite structure and the PTR measurement scheme has been developed and subsequently the thermal-wave field has been derived. The characteristics of the thermal-wave field with respect to the thermal diffusivity of the material, the diameter of the sample, the size of the incident beam, and the measurement of the angle are discussed. The Green function method provides a way of evaluating thermal-wave fields of bi-layered spherical structures with arbitrary intensity distributions of incident laser beams, which is otherwise difficult with other methods.
Keywords: photo-thermal radiometry, Green function, bi-layered spherical structure, infrared technique

Fringe Pattern in Ultrasonic C-scan Image OF c-Sandwich Structure
Guo Guangping
NDT Lab, Beijing Institute of Aeronautical Materials
(PO Box 81-6, Beijing, 100095 China)
Abstract: A strange fringe pattern was found when a C-sandwich composite part was inspected with through transmission ultrasonic C-scan method. Dark fringes appear in C-scan image, which look like optical moiré phenomenon. Generally speaking, dark area in the image corresponds to high acoustic attenuation and could be interpreted as defects of de-bonds or de-laminations. Since the pattern has regular appearance, structure factors should be considered rather than defects. At the area fringe pattern appears, two layers of honeycomb in C-sandwich structure were placed in parallel direction. Computer simulation was used to simulate the superimposition of the two layers of honeycomb. Optical moiré phenomenon caused by overlapping of honeycomb cell’s wall can be found when two layers were placed in parallel direction. No moiré exists when the two lays placed in cross direction. Then, a sample of C -sandwich structure sample was manufactured whose two lays of honeycomb were placed in the parallel direction. Moiré phenomenon was found again in its TTU C-scan image. X-ray radiographic inspection results of the specimen show good agreement between ultrasonic attenuation and overlapping of honeycomb cell’s wall. In conclusion, different overlapping of honeycomb cell’s wall is the reason of fringe pattern in C-scan image.
Keywords: C-sandwich, composite, Moiré, ultrasonic

Research on WEB Based Remote Intelligent NDE System
Guo-Fu Yin1, Han-Bing Yan1, Ying Yin2, Gui-Yun Tian2
1. School of Manufacturing Science and Engineering, Sichuan University, Chengdu. 610065. PRC.
2. School of Electrical, Electronic and Computer Engineering, University of Newcastle upon Tyne, NE1 7RU, UK
Abstract: Based on combining network technology, data processing technology, artificial intelligent technology, and dynamic web page technology, the Remote Intelligent UDE System for nondestructive testing is constructed. Clients can realize identification, classification, diagnosis of the detected flaws via internet and formulate manufacturing technological procedure according to the results of the system. The structure and function module of the system are proposed and the key intelligent technology, such as data compression for remote transmission, data processing algorithm in the system is introduced. Finally, the feasibility and validity of the RDMSS are illustrated.

Discussion for parameter calculated mode of circular seam eccentricity internal transmittance
N, L3 and Leff by crack detector with directional and circumferential ray
GU Qin
(Zhangjiagang Branch, Jiangsu Special Equipment Safety Supervision and Inspection Institute, Zhangjiagang 215600,China)
Abstract: As to the schoolbook of radiographic test, the calculated formula for every transmitted length of circular seam eccentricity internal transmittance should be extensional analyzed. Also the use of crack detector with directional or crack detector circumferential ray should adopt different formulas.
Keywords: radiographic test;circular seam internal transmittance eccentricity;formula analysis;effective half-angle of radiation;transmitted length

Research of Online Automated Detection Method for the Assembly
Correctness inside Mechanical Products
Han Yueping1,2+, Han Yan1,2, Li Rui hong1, Wang Li ming2
(1 National Key Laboratory For Electronic Measurement Technology, Taiyuan, Shanxi, 030051, China; 2 Key Laboratory of Instrumentation Science & Dynamic Measurement (North University of China), Ministry of Education, Taiyuan, Shanxi, 030051, China)
Abstract: This paper proposes an effective approach for online automated inspecting and recognizing the assembly structures inside complex products using multiple views technique and X-ray digital radiography (DR) system. The paper uses a Vertical Hybrid Projection Function (VHPF) as the feature of recognition. VHPF combines integral projection function and standard deviation function so that it can reflect the mean and the variance of the pixels in vertical direction of the image. Using whole-orientation features of the objects in circumference, the issue of blind area of recognition is well solved in this paper. Based on this approach, the first domestic “multi-view” X-ray DR detection system was developed, and it is successfully applied in online detecting some axial products which assembly structures are complicated.
Keywords: online automated inspection, vertical hybrid projection function, assembly structure inside product.

Thermal properties of nano-scaled bi-layer films deposited on
substrate characterized by transient grating technique
Heng-yi Ju, Pao-Kuang Kuo, Shu-yi Zhang, Zhe Li and Di Ma
Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093, China
Abstract: Thermal properties of thin films with nano-scaled thickness (100 ~ 200 nm) deposited between cover films (~ 50 nm) and silicon substrates (~ 700 µm) are characterized by nanosecond transient grating technique. In the technique, an 8 ns pulsed laser is utilized as the excitation source to produce transient grating on the multilayered materials and a continuous He-Ne laser is used as the detection source, which is incident on the surface of the sample and diffracted from the grating. The 1- order diffraction beam is detected by a photomultiplier, and the output signal expresses the thermal decay process within the multi-layer structures. To simulate the thermal behavior of the multi-layered structure irradiated by the transient grating, a 2-D multi-layered thermo-diffusion equation is analytically solved by an eigen-function expansion method. These solutions can be calculated numerically based on the experimental conditions, and then applied to fit the experiment results, by which the thermal diffusivities of the bi-layer films deposited on a substrate can be evaluated. In the calculations, the multi-parameter fittings are considered. The calculated results show that the thermal diffusivities are dependent on the thicknesses or deposition conditions of the nano-scaled films.
The results demonstrate that the combination of the described nanosecond pulsed laser experiment and eigen-function solution theory are useful for evaluating the thermal properties of nano-scaled bi-layer films.
This work is supported by National Natural Science Foundation of China, No. 10574073.

Reconstruction of depth profile of thermophysical properties of case
hardened steels using photothermal technique
Hong Qu1, Chinhua Wang1*, XinXin Guo2, and A. Mandelis2
1. Key Lab of Modern Optical Technologies of Jiangsu Province, Institute of Modern Optical Technologies, Suzhou University, Suzhou, Jiangsu 215006, P. R. China
2. Department of Mechanical and industrial Engineering, University of Toronto, Toronto, Canada, M5S 3G8
Abstract: A new method of retrieving thermophysical depth profile of continuously inhomogeneous materials is presented both theoretically and experimentally using photothermal radiometry technique. A 3D theoretical model which is suitable for characterizing materials with continuous varying thermophysical parameters of arbitrary depth profile is developed. A numerical fitting algorithm to retrieve the thermophysical profile was demonstrated with three case hardened steel samples, which are found to be in good agreement with the hardness profile obtained with conventional indent method.
Keywords: reconstruction, depth profile, thermophysical properties, photothermal radiometry

Registration of X-ray Real-time Image Sequences for Weld Inspection
Hou Runshi, Du Dong, Shao Jiaxin, Chang Baohua, Wang Li
Key Laboratory for Advanced Materials Processing Technology,
Ministry of Education, P. R. China
Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
Abstract: Real-time X-ray inspection is one of important nondestructive testing method for long consecutive weld. Registration of the image sequences can be used for the algorithms which need the position relation between image sequences, such as multi frame superposition to reduce noises, removal of motion blur and defect tracking in image sequences. However, the image registration is difficult because the signal-to-noise ratio of real-time X-ray weld image is rather low and the image is quite similar along the weld direction. In this paper, the image registration processing is separated into rotation registration and translation registration. The slope angle of weld, which is calculated by weld edges, is used to implement the rotation registration. By extracting features from difference image, the translation registration is implemented based on phase correlation. The experimental results show the proposed method is stable and precise.
Keywords: real-time X-ray image, weld inspection, image registration, phase correlation

Background Subtraction Segmentation of Weld Defects in X-ray Image Based on Partial Surface Reconstruction
Hou Runshi, Du Dong, Shao Jiaxin, Wang Li, Chang Baohua
(Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, P. R. China
Department of Mechanical Engineering, Tsinghua University, Beijing 100084)
Abstract: Background subtraction is often adopted in automatic weld defects inspection techniques based on real-time X-ray images. The key to this method is estimating of weld background, and it is mainly realized by low-pass filter or curve fitting methods. Generally, there are many false alarms and inaccurate defect shape due to inaccuracy of weld background obtained by these methods. In this paper proposes a new background subtraction based on partial surface reconstruction is proposed. Firstly, the possible defect positions are identified by gray-level wave analysis, and then weld background is estimated by reconstruction in these areas. Results show that false alarm and missed detection are decreased effectively, and the defect shape is more accurate.
Keywords: weld defects, radiography testing, background subtraction

Hu Binding, Liu Jinping
(Industrial Equipment Installation Co. of CSCEC No.8, Nanjing 210046)
Abstract: For solve testing information transfer veracity and smooth and share, we suggest that using radio-frequency and electron label technology to serve as carrier  for disposal software of welding and testing information. by feasibility analysis, this technology accord with the demand of welding and testing process control, and economy, and become fact at net and digital disposal.
Keywords: Radio-frequency Testing Software of NEWS Disposal

Hu Binding Liu Jinping
(Industrial Equipment Installation co. of CSCEC No.8 Nanjing 210046)
Abstract: NEWS system is running for info of welding and nondestructive testing that base on computer technology, for ensuring the quality of petrochemical device which piping systems are anfractuosities,and welding and nondestructive testing are very difficult. Herein, discussing the birth, the present status, the function and the development of this system.
Keywords: Weld Non-destructive testing Info

HUA Yun-song1 ,SUN Da-le2 ,FAN Qun2 ,YAO Li-song2
(1. College of Optics and Electron Information Engineering; USST; Shanghai 200093 China;
2. Technology Center; Baoshan Iron and Steel Co.; Ltd.; Shanghai 201900; China)
Abstract: In this paper, compared and analyzed with the existing residual stress measuring techniques, an ultrasonic stress measuring technology based on the critical refracted longitudinal (LCR) wave is put forward and used to measure the stress. An ultrasonic stress measuring system based on the LCR wave, which adopt the mode of “one sending and two receiving”, was set up to measure and analyze the stress. The stress of circular flat-plate 5%Cr was tested with the ultrasonic stress measurement method and other two mature methods (i.e. X-ray diffraction method and pin hole method) respectively. Contrasted three measuring results, it shows the ultrasonic stress measuring method based on the critical refracted longitudinal wave can be used to measure the stress of roller.
Keywords: Ultrasonic stress measuring method; Critical refracted longitudinal wave;X-ray diffraction method; pin hole method

A Computer Implementation of Space Debris Impact on Spacecraft Using Acoustic Emission
Huang Zehuan, Liu Wugang
(Beijing Institute of Structure and Environment Engineering, Beijing, 100076)
Abstract: The paper introduces a computer implementation of space debris impact on spacecraft using acoustics emission. Using Wavelet Toolbox of Matlab, the signal will be decomposed and be re-builded. Using correlation analysis, we are able to find the time difference; Use plane triangle location formula, we can find the location result.
Keywords: Acoustic emission; Matlab; Wavelet analysis; correlation analysis; time difference location

A Discussion on Acoustic Emission Technology Application to Multilayer Binding Pressure Vessel Inspection
HUANG Zhen-Hai
Shanghai Baosteel Industry Inspection Corp., Baoshan, 201900, Shanghai
Abstract: In this paper, some problems that will encounter in the Acoustic Emission (AE) inspection to multilayer binding pressure vessel, have been discussed duo to its features. It have been proposed that time difference two-dimensional location method is not suitable for the active defects test in multilayer binding cylinder of multilayer binding pressure vessel, while the linear location method with sensor located near the thick hoop weld joint is a better choice for this test due to the strength and activity of the defect signal, and the time difference two-dimensional location method is the best method for the head AE test, the reason for these have been given. Some advices have been provided for the flaw signal handling.
Keywords: Multilayer Binding Pressure Vessel, Acoustic Emission, Test, Inspection

The ultrasonic examination for T-type welded joint of overhead and gantry cranes
Ji li ming
Jiangsu Province special equipment safety supervision inspection institute Wuxi branch
Abstract: Because the crane working conditions are bad, and frequently withstands various load function again and again, so the welding quality of main stress structure directly influence to crane's safe operation. This article mainly aims at the main stress structure of overhead and gantry cranes which ultrasonic examination for T-type fusion penetration welded joint to carry on the summary analysis.
Keywords: overhead and gantry cranes, main stress structure, T-type welded joint, ultrasonic examination

The research of extracting information of ESPI fringe pattern
JIANG zhaofang1 LIANG hua2 WANG haitao1 LIANG bin2
1 Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;
2 Nanjing Boiler &Pressure Vessel Supervision and Inspection Institute, Nanjing 210016, China;
Abstract: The electronic speckle pattern interferometry (ESPI) is applied widely in non-destructive technology( NDT),optical rough surface displacement,strain and vibration. To process and analyze the ESPI fringe patterns,we can obtain the deformation of the measurement field and get the stresses and strains. Some central processing techniques for interference-stripes analysis are introduced. Such as phase-shifting method, gray level method, Fourier Transform method, fringe center method. The method based on fringe refinement algorithm is particularly introduced before the ESPI fringe patterns are of pretreatment. The thin skeletons are amended to smooth. The method can automatically pick up the fringe skeletons precisely and rapidly. And we use the thin skeletons technique in non-destructive technology ( NDT), detect and analyze the flaw of honeycomb -structure materials.
Keywords: ESPI, Interference-stripes, image processing

Development of AC Automatic Fluorescent Magnetic particle flaw detector with Image Displaying
Jin jing-hua1, Zhang qing-xin1, Li ling1, Chen jian-sheng2
(1. Shenyang Dongji Industry Group Co. Ltd., Shenyang Liaoning 110045, China;
2. ZETEC (Beijing )Non-detective Testing Equipment Co. Ltd., Beijing 100101, China)
Abstract: The operating principle, composition, characteristics of performance and main technical index of a kind of AC automatic fluorescent magnetic particle flaw detector with image displaying were introduced in this paper. The equipment had very important practical value in magnetic particle testing for the steel pipes, axles, poles and the bullet-rocket system of the national weapon industry.
Keywords: Fluorescent magnetic particle flaw detector;Image displaying;Automatic control;development of magnetic particle flaw detector

Study on a filter back-projection reconstruction Algorithm of unconventional CT
Jin Yong, Wang Zhaoba
Key Lab on Instrumentation Science and Dynamic Measurement of the Education Ministry,
North University of China, ShanXi Taiyuan,030051,China
Abstract: Conventional X-ray Industrial CT is well known as a non-destructive testing method for technical components. Unfortunately there is no possibility to reconstruct the slice image of the industrial piece with large and flat size using conventional CT. So unconventional CT scanning method was introduced to obtain a two-dimensional projection image, and infers a filter back-projection reconstruction algorithm. To demonstrate validity of this method, a common flat piece and flaws are simulated. 3-D image of flat piece is reconstructed based on filter back-projection reconstruction algorithm.
Keywords: Flat piece, unconventional CT, filter Back-projection, 3-D reconstruction

Ordered-Subset Ridge Regression in Image Reconstruction
Jinxiao Pan1, 2, Yan Han1, Liping Liu2 and Tie Zhou2
1. National Key Laboratory For Electronic Measurement Technology,North University of China, Taiyuan, Shanxi, 030051, China
2. LMAM, School of Mathematical Sciences, Peking University, Beijing, 100871, China
Abstract: Weighted linear regression method has been widely applied for image reconstruction in computed tomography. We propose an approach based on the ridge regression method and derive two ordered-subset reconstruction algorithms from this framework. The convergence property of the algorithms are validated by recent results on the ordered-subset Landweber scheme or numerical experiments. We also extent the strategy for formulating effective ordered-subset partitions based on the previous research studied by Jinhua Sheng. Numerical simulation and application to practical data demonstrate the performance of the proposed algorithms and ordered-subset strategy.
Keywords: Computed tomography; ridge regression; iterative algorithm; ordered-subset.

On line detection of Transformer Fault based on FTIR
Kang Jian-shuang, Jiang Shu-bo, Cheng Ming-xiao
(Automation College, Nanjing University of Technology, Nanjing, 210009, China)
Abstract: Transformer is a very important power transmission equipment whose working condition directly affects the safety level. Using the method of the Fourier transformer for the qualitative analysis of the character of the fault gas and then using the wavelet transform and BP neural network for the quantitative analysis of the characteristics of the fault gas determine the operational status of the current transformer. So effectively monitoring the function of the transformer, accurate judgment of the potential failure or hidden danger is of great significance.
Keywords: transformer fault, FTIR on-line monitoring, BP neural network

Characteristic and advantage of phase-array ultrasonic imaging technique in the detection of butt weld joints
Li Haihua, Zhao Lifan, Tang Feiyang liang, Guo Xingjian
Pressure-vessel Inspection Institute of DuShanZi Petrochemical Corporation Petro-China
Abstract: Characteristic of phase-array ultrasonic imaging technique in the detection of butt weld joints was introduced in this paper. And for comparison,many kinds of other detection technologies were applied in the detection of butt weld joints to analyze and study the advantage of phase-array ultrasonic imaging technique.
Keywords: steel butt weld joints,X-Ray detection technology,routine ultrasonic inspection and measurement,TOFD ultrasonic inspection technology,phase-array ultrasonic imaging technique

The possibility analyzing of AE in missile engineering
Li Hongjun Fang Jianqin Zhao Ye
PLA 96411 unit
Abstract: This paper introduces the AE and it’s detection in brief, and analyses the possibility in missile engineering.
Keywords: AE, missile, applications

Detection of graphite balls for the fuel handling system in a high temperature gas cooled pebble bed reactor using eddy current testing
Li Dong, Sun ZhenGuo, Chen Qiang
(Key Laboratory for Advanced Materials Processing Technology,
Department of Mechanical Engineering, Tsinghua University, Beijing 100084, P. R. China)
Abstract: It is critical for the normal operation of a high-temperature gas-cooled pebble bed reactor (HTGR) to accurately monitor the number and direction of the fuel balls passing through the fuel handling system. In this paper, a new through-transmission eddy current testing probe has been put forward to play the role of graphite balls detector. The probe’s electromagnetic FEM model has been established so as to study the factors affecting the performers of the probe. On this basis, electromagnetic detection parameters and probe designs have been optimized. According to the results of analysis, a bidirectional detector for the fuel ball handling system of HTGR has been fabricated. The experimental results confirm the validity of the FEM model, and show that the detector works accurately and reliably, which meets the requirements of application in HTGR.
Keywords: eddy current testing; fuel ball detecting; FEM model; HTGR;

Ultrasonic testing on the trailer cylinders of the compressive natural gas station
Li Honglei
Beijing Special Equipment Inspection & Testing Centre
N0.3 Huixin East Street, Chaoyang District, Beijing 100029
Abstract: It’s directly related to the city safety to have the trailer cylinder of the compressive natural gas station well-operated. The writer summarized that the ultrasonic testing is the best choice for the in-service inspection of the trailer cylinder. Regarding the confirmation on the sensitivity of the UT, it could be tested by the homemade reference block, simulating the disfigurement via the cut line flute, and further considering about the attenuation. For the circumferential transverse wave testing on the outside surface, the outer-circumferential dual-hole calibration instruments could be used to solve those difficulties on the calibration of the refraction angle, the fixation of the front distance, and the adjustment of Scanning speed etc.
Keywords: Vessel forging, the ultrasonic testing, the testing on the circumferential of outside surface, reference block for calibration, working sensitivity

Measuring the Direction of Displacement Vector by Holographic Method
Li Ji-ping Liang Da-kai Cai Yun-liang
(Aeronautical Science Key Lab. for Smart Materials & Structures, NUAA
29 Yudao Street, Nanjing 210016, P. R. China)
Abstract: Direction is one important factor of the displacement vector. A method for measuring displacement direction of object, called the reference-object holographic method, is proposed in this paper. The reference-object is put next to the measured object. Two double exposure holograms of the two objects are recorded on the same plate. One is the hologram of the measured and the reference objects modulated by the plate displacement. The other is non-modulated hologram of the measured object and reference object. The former is used to analyze direction of displacement vector of measured object. The latter is used to measure the magnitude of displacement vector. The principle of this method is described here. Results of experiment are given. It is shown theoretically and experimentally that the proposed technique is effective.
Keywords: reference-object, holographic method, direction, nondestructive testing

Thickness and Roundness Evaluation of PE Pipe By Multi-channel ultrasonic Technique
Li Xiaoli, Tao Ning, Liu Wenxia, Shen Jingling, He Fengqi, Feng Lichun, Zhang Cunlin
(Capital Normal University, Beijing 100037)
Abstract: In this paper, broadband ultrasonic test for large diameter PE nondestructive inspection was studied and designed considering that quality of the thickness and diameter of polyethylene pipe should be controlled. Besides, the test system was introduced. The technologies proposed in this paper have practical significance for improve quality and credibility of PE production and inspection.
Keywords: ultrasonic test, inspection of PE pipe, thickness control, roundness

Introduction and Evaluation of ASME Code Case 2235-9
LI Yan
(Jiangsu Taihu Boiler Co., Ltd, Wuxi 214187, China)
Abstract: The recent ASME Code Case 2235-9 was introduced and evaluated,involving the comprehensive technical requirements and acceptance criteria of ultrasonic TOFD inspection of the butt welded joints in pressure equipment. The intention is to provide reference frame of applying the new technique in our country.
Keywords: Pressure equipment;Ultrasonic inspection;TOFD technique;Procedure requirements; Acceptance criteria

Worldwide Trend of Phased Array Ultrasonic Testing
LI Yan
(Jiangsu Taihu Boiler Co., Ltd, Wuxi 214187, China)
Abstract: The worldwide trend of phased array ultrasonic testing technology in application and standardization was introduced, including some of the typical application examples such as inspection of butt-welded joints in atomic-electric power equipment, boilers, spherical tanks, pipelines and small diameter tubes etc. The importance of preparation of calibration blocks and welding samples and the performance demonstration was emphasized. The intention is to provide a reference to spreading the new technology of phased array all around our country.
Keywords: Ultrasonic testing;Phased array;Standardization; Calibration blocks;Performance demonstration

Discussion On the vocational education of Non-destructive testing
(ChangSha Aeronautical Vcational and Technical College, ChangSha, Hunan 410124)
Abstract: Based on the new conception of vocational education, put forward that the reform of non-destructive testing of vocational education must combine theory with practice,set vocational activities as a guide, regard students as the main body, and regard knowledge、theory and practice as an integral whole in professional teaching. The main aim of vocational teaching is training student's ability of solving practical problems.
Keywords: non-destructive testing; vocational; education; reform

MMM Signals of Stress Concentration Detected in Different Magnetic Environment
Liqiang ZHONG1, Luming LI2, Xing CHEN3
12 School of aerospace, Tsinghua Univ.
3Department of mechanical engineering, Tsinghua Univ., Beijing, 100084, China
Abstract: Since metal magnetic memory (MMM) method was promoted by Dubov in 1990s, it has become a focus of interest to nondestructive testing researchers as a result of its ability to evaluate stress concentration status without artificial magnetization. However, because of its high sensitivity, the magnetic field becomes an important influencing factor during detection. In different magnetic environment, there will be different results caused by the same stress concentration. This paper investigates the relationship between the MMM signals and the magnitude of magnetic field with experiments in which the magnetic distortion caused by stress concentration in zero magnetic field but detected in different magnetic environment. The result shows that the testing result depends both on the magnetic environment and stress concentration status. It means in different magnetic field, the MMM method can still detect the stress concentration roughly, but impossible to evaluate the magnitude of the stress concentration, particularly without considering the influence of magnetic environment. But the result also supports a potential method we suggested in our previous work: to get a more reliable evaluation of stress concentration with multi-magnetic field during detection.
Keywords: Nondestructive Evaluation, Metal Magnetic Memory, Environmental magnetic field,

Numerical Simulation of Acoustic Emission Signal Produced by Hypervelocity Impact on Aluminum Plate
LIU Wugang, HUANG Zehuang, LIU Yubei, ZHANG Hui
(Beijing Institute of Structure and Environment Engineering, Beijing, 100076)
Abstract: In order to ensure the astronauts’ safety and spacecraft normal operation, the design of sensor systems to detect impact impacts on spacecraft become an important problem of spacecraft design. The numerical simulations of acoustic emission (AE) signals produced by projectile hypervelocity impact on Aluminum plate at normal have been carried out using the SPH (smoothed particle hydrodynamics) technique of AUTODYN hydro-codes in this paper. The results using two dimensional simulations are given. In order to separate the characteristics of different wave modes, the AE signals are divided into low frequency and high frequency parts by wavelet time-frequency transform and reconstruction. The results show that the damage condition of the spacecraft can be represented by the amplitudes of the reconstructed the impact signals.
Keywords: space debris; hypervelocity impact; acoustic emission; numerical simulation

Study on Ion Implant Dose Monitoring by Photocarrier Radiometry
1Liu Xianming, 1Li Bincheng, 2Zhang Xiren
1(Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209)
2(School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054)
Abstract: The application of photo-carrier radiometry (PCR) to the ion implant dose monitoring is reported. The dependence of PCR signal amplitude on 11B+ and 31P+ ion implant dose in silicon wafers is analyzed as a typical case.
Keywords: Photo-carrier; Ion implant; Radiometry; Implant dose

Application of Acoustic Emission Technique to the Static Test of Composite material Structures
LIU Yan-tao, LIU Wu-gang, ZHANG Hui, LI Yue
(Beijing Institute of Structure and Environment Engineering, Beijing, 100076, China)
Abstract: Characteristics of acoustic emission (AE) technique to composite and its main parameters are both expounded, and the identification of damage defects is described with AE technique. The static test processes of the filament-wound case are supervised with AE technique. Moreover, the relation between AE signals and the three damage mode of composite with the external-pressure load increasing is analyzed. These indices provide rich experimental information for the application of AE technique to the static test of composite material structures.
Keywords: Acoustic emission (AE) technique composite material static test defects detect filament-wound case

The Development of a Space Debris High-velocity Impact Data Acquisition System Based on LabVIEW
Liu Yantao, Liu Wugang, Sun Fei, Liu Yubei
(Beijing Institute of Structure and Environment Engineering, Beijing, 100076, China)
Abstract: Real-time data acquisition system used acoustic emission (AE) sensors could provide early warning to the treat of impact to spacecraft from space debris. In this paper, the design and development of a high-speed data acquisition system with Graph-Language LabVIEW 7 are introduced. It has the superiority that the real-time waveform displaying, data acquisition and storage. Experiments show that the response is sensitive, the precision and stability of this instrument are higher, and the interface of man-machine is friendly.
Keywords: space debris, high-velocity impact, virtual instrument, LabVIEW, acoustic emission (AE)

Application of Infrared Imaging Technology on Special Equipment Inspection and Damage Diagnosis
Liu Yanming, Hu Binbin
Shanghai Sumfar Technology Co., Ltd.
Abstract: The technology and application situation of Infrared Thermography were briefly introduced in this paper. By examples of infrared inspection, the application of Infrared Imaging Technology on special equipment inspection was introduced.
Keywords: Preventive Predictive Maintenance Diagnosis Energy Efficiency Infrared Thermography

A Design Proposal for High Speed Impacting Single of Data Acquisition System Based on PCI1714
LiuYubei, LiuWugang, HuangZehuan, LiuYantao
(Beijing Institute of Structure and Environment Engineering, Beijing, 100076)
Abstract: A design proposal for high speed impacting single of data acquisition system. The system used Advantech PCI-1714 which drive and control of programs developed with Microsoft Visual C++. This makes data acquisition, data transfer and data storage available.
Keywords: PCI-1714; High Speed Impacting Single; Data Acquisition; Advantech DLL Driver; VC++

The Research for Characteristic of Acoustic Emission form Carbon/Epoxy Composite When going through Three-point-bending
Long Xianhai Wang Hangong Yang Nengjun
(xi’an high technology institute, xi’an, 710025 )
Abstract: The three-point-bending sample which is made from Carbon/Epoxy Composite is loaded, and its acoustic emission is detected by the equipment of ANSY-5. The experiment shows that the hit number of acoustic emission signal can describe the damage process of the composite sample; the repeat loaded experiment illuminate that Felicity phenomena is obvious for the composite.
Keywords: acoustic emission, composite, three-point-bending

Discussion of a new technology about radial test of super critical boiler
Long Yi1, Chen-Hongdong
(Hunan Electric Power Company Test & Research Institute, Changsha, 410007, China)
Abstract: Aiming at the structure of super critical boiler, it is expatiated particularly the peculiarity & routine technology about radial test. On the basis of radial testing results, it is discussed the new technology about radial test, and prove that there is guidance significance of the inspection and maintenance on boiler.
Keywords: super critical boiler, radial test, discussion

A study of surface breaking crack evaluating by using Scanning Laser Source-Dual Laser Source technique
Ni Chenyin, Wang Lijuan, Shen Zhonghua1, Lu jian and Ni Xiaowu
Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, People's Republic of China
Abstract: A hybrid non-destructive surface breaking crack evaluation technique of Scanning laser source technique and dual laser source technique is presented and studied. By using this technique, surface breaking crack information, like location, depth and orientation can be measured in one measuring cycle. First, the scanning laser source technique is employed to obtain the location information by detecting the characteristic changes in the amplitude content. Then the dual laser source technique is utilized to detect the arrival time of corresponding ultrasound mode, so the crack depth and orientation can be calculated. Furthermore, the diffracted and reflected ultrasound modes are studied by FEM when crack orientation varies in order to reveal the relationship between these ultrasound components and the crack orientation.

“Exception evaluation”for Nondestructive testing
NING-Dongming WANG- Wuwei
(Hunan Xiangdong Chemical Machinery Co, Ltd, Zhuzhou 412300)
(Shanghai Nuclear NDT Center, Shanghai 200233)
Abstract: “Exception evaluation” is a new term which is put forward by author, the new term is extended from exception testing” in the second version of《radiography testing》 textbook. The result may be not precise with the regular evaluation methods in the application of the practice production, even affecting the safe using of the products and taking a serious result. The introduction of the“ exception evaluation ”can well interpret the result of the evaluation, and then promoting the development and perfection of the nondestructive testing technology
Keywords: Exception evaluation; pressure vessel; round flaw; stripy flaw

Characterization of Thermal property of Materials by Infrared Thermography
Peng-fei Qiu, Shu-yi Zhang, Zhao-jiang Chen, Zhong-ning Zhang and Xiu-ji Shui
Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093, China
Abstract:An infrared thermography is used for non-contact characterizations of thermal properties of materials. In the experiment, a pulsed laser is used to excite a transient thermal source in the material and an infrared camera system is used to record the infrared thermo-images of the subsequent heat diffusion and heat loss processes. In the theory, by solving heat conduction equation, a two-dimensional thermal distribution function produced by the pulsed laser can be obtained. Then, based on the relations between both two-dimensional thermal distribution functions extracted at any two times, the thermal diffusivities and heat loss rates of the materials can be obtained by fitting the theoretical calculations to the infrared images recorded at both different times. The results indicate that this method is useful to determine the thermal diffusivity and thermal loss for industrial non-metallic materials with rough surfaces and/or inhomogeneous micro-structures.
Keywords: Thermal diffusivity; pulsed laser; infrared thermography, industrial material

Quantitative Reconstruction of Stress Corrosion Crack by Using a Neural Network Strategy
Qiang Geng, Li Wang and Zhenmao Chen
(MOE Key Laboratory for Strength and Vibration, Xi’an Jiaotong University, Xian, 710049, China)
Abstract: As stress corrosion crack mainly propagates along the boundary of crack, it has a very complicated microstructure similar to the branches of a tree, which makes its nondestructive quantitative evaluation more difficult. In this paper, a method for SCC modeling SCC and a sizing scheme based on neural networks were introduced and evaluated. Impedance signals from a pancake probe scanned just over the crack were taken as the source signal for crack reconstruction. A lot of sample datasets were calculated by using a FEM-BEM hybrid code for network training. A parameterization method of crack for the output of Neural Network was introduced. The numerical results demonstrated that the Neural Networks approach is a suitable way for reconstruction of SCC.
Keywords: Stress Corrosion Crack; Neural Networks; Modeling; Reconstruction

Application of Leakage Magnet Detection Technology on Nondestructive Testing of Steel Wire Ropes
Qiu Faju, Cao Guangmin
(Ningbo Special Equipment Inspection & Testing Center, Ningbo 315020)
Abstract: The theory of Leakage magnet testing and the main defect types of steel wire ropes are introduced. Basing on analyzing defects of a segment,its types and characters are pointed out. And in the end,this paper discusses the extant drawbacks of leakage magnet testing of steel wire ropes.
Keywords: Leakage Magnet;Steel wire rope;Broken wire;Nondestructive testing

Building the Specialty of Characteristic and Making Contribution to the Development of NDT Technology
Ren Jilin, Dai Jiyang, Lu Chao
Nanchang Hangkong University, Nanchang, 330063
Abstract: The thirty years’ construction history of non-destructive testing specialty in Nanchang Hangkong University is introduced in this paper. And the following aspects are mainly included, the specialty origin, development of specialty construction, experience of construction and its prospect. The history of NDT higher education and the contribution to the progress of NDT technology in our country are partly reflected during the course.
Keywords: non-destructive testing, higher education, specialty construction, talents cultivation

Quantitative NDT of Metallic Foam Based on Direct Current Potential Drop
Shejuan XIE, Shaodi LI, Qiang GENG, Zhenmao CHEN
(MOE Key Laboratory for Strength and Vibration, Xian Jiaotong University,Xian, 710049,China)
Abstract: In this paper, a method of quantitative NDT of metallic foam was developed on the basis of the Direct Current Potential Drop (DCPD). A feed forward Neural Network (NN) is applied for the inverse mapping in addition with a Principal Component Analysis (PCA) process. To cope with the huge computer burden necessary to generate training data of NN, a novel fast forward solver based on FEM and databases of unflawed field information is proposed for the rapid computation of DCPD signals. The numerical results indicate that the quantitative NDT of metallic foam can be performed by using Neural Network and the proposed fast solver can significantly decrease the computer resources but with a high accuracy.
Keywords: Metallic Foam, Quantitative Nondestructive Testing, Neural Networks, Fast Solver

Study on Visualization of Guided Waves Propagation Simulated in Defect Pipes
Shen Chuan-jun, Wang Yue-min, Sun Feng-rui
(College of ship and power, Naval University of Engineering, Wuhan 430033,China)
Abstract: The propagation of guided wave in pipe with hole is simulated by building the three-dimensional finite element model of guided wave in pipe, and applying longitudinal ultrasonic to the pipe end by using the finite element method. The velocity of the longitudinal ultrasonic is calculated from the time of the reflected echo signals which is agreed very well with the velocity calculated from the dispersion curve. The attenuation and refection of the guided wave propagation in pipe is indicated from the echo signals obtained from the observation point. The simulated visualization of guided wave propagation in pipe is realized and the process is indicated intuitionistic by the animation. This research will make it easily to explain the dispersion and reflection features of the guided wave in the use of nondestructive testing in pipes.
Keywords: guided wave, pipe, propagation, visualization

Eddy Current Testing of Austenitic Stainless Steel Heat Exchanger Tubes
Shen Jianmin, Qiu Faju, Wang Xiaohua
(Ningbo Special Equipment Inspection Center, Zhejiang, Ningbo, 315020)
Abstract: This paper analyzes and verifies eddy current signals of austenitic stainless steel heat exchanger tubes, and then compares natural defects with artificial defects. And in the end, benefits of eddy test for heat exchanger tubes are discussed.
Keywords: eddy current, heat exchanger tubes, signals, defects

Several False Defect Signals in Acoustic Emission of Pressure Vessels
Sun Lei, Shen Jianmin, Mao Guojun, Wang Xiaohua
Ningbo Special Equipment Inspection Center, Zhejiang, Ningbo, 315020
Abstract: Several false defect signals in acoustic emission of pressure vessel like the vibration noise, electromagnetic noise, corrode outcome splitting and the friction between backing board were introduced. Frequency analysis of these signals was conducted. We can find the different signals by frequency.
Keywords: acoustic emission; noise; false defect signal; frequency analysis

BLC-8Z Ultrasonic Automatic Detecting System for Locomotive and Vehicle Axels
Sun ZhenGuo[1] Huang Cao[1] Zhi Zhengxuan[1] Du Xuegang[2]
(1 Key Laboratory for Advanced Materials Processing Technology, Department of Mechanical Engineering, Tsinghua University, Beijing, 100084;2 Beijing BOLICA Mechanics & Electronics Development Co, Ltd.
Abstract: Based on the criteria of TB/T 1618-2001 (Ultrasonic Test of Locomotive and Vehicle Axels), a novel BLC-8Z Ultrasonic Automatic Detecting System for Locomotive and Vehicle Axels has been established. With 8-10 channels of detectors divided into 2 groups, the radial surface of axels is scanned in a spiral trace. Automatic flaw detecting process is accomplished with the synergic operation of a PLC (carrying out detecting process control , a high-speed DAS card ( carrying out ultrasonic signal sampling ) and a IPC (carrying out flaw diagnosing and human-computer interaction). Functions of axel type information input, automatic generation of detecting actions, real-time recording and dynamic displaying of reflected waveforms, flaw diagnosing with threshold criteria or DAC criteria, print of report forms are integrated in the developed system.
Keywords: Locomotive axels; Ultrasonic automatic flaw detecting; PLC; flaw diagnosing

A Prediction of brazed residual stress in stainless steel plate-fin structure based on neural network
Tang Guizhong1,2 Jiang Wenchun2 Gong Jianming2 Zhang Guangming1
1) School of Automation, Nanjing University of Technology, Nanjing 210009
2) School of Mechanical and Power Engineering, Nanjing University of Technology, Nanjing 210009
Abstract: It is quite difficult to predict brazed residual stress in stainless steel plate-fin structure because of many factors considered. This paper presents a brazed residual stress predicting method based on neural network for stainless steel plate-fin structure. Main factors of bringing forth residual stress are obtained to construct input vectors for neural network by finite element analysis. Afterwards, a predicting model is established by neural network. To evaluate the predicting performance of the model, the brazed technologic course of stainless steel plate-fin structure were simulated by using the model. The results showed that the method could predicting effectively and efficiently brazed residual stress in stainless steel plate-fin structure.
Keywords: Residual Stress; Stainless Steel Plate-fin Structure; Brazing; Neural Network

Low Pass Effect of Surface Defect Metal based on Laser Ultrasonic
Wang Jingshi[1] Xu Xiaodong[1] Liu Xiaojun[1] Xu Gangcan[2]
1 Key Laboratory of Modern Acoustics of MOE, Institute of Acoustics,
Nanjing University, Nanjing, 210093
2 Hanzhou Applied Acoustics Research Institute, Hanzhou, 310012
Abstract: The traveling properties of laser-generated surface acoustic wave with broad bandwidth, which propagated on a surface defect sample, have been investigated in theory. The numerical results of theoretical models with different defects indicate that the surface defects worked as low-pass filter for the travelling surface acoustic waves, the cut-off frequencies of low-pass filter is linearly related to the depth of the defect, and decreased against to the increasing depth of the defect. The amplitude of the traveling surface acoustic wave is powerfully attenuated by the width of surface defect. The numerical results provide a theoretical basement for quantitative detection of the surface defects.
Keywords: Laser Ultrasonic; Surface Acoustic Wave; Finite Element Method; Low-pass Filter

Wavelet Analysis and its Application in the Field of Signal Processing for Acoustic Emission
Wang Li Min
(Beijing Institute of Structure and Environment Engineering, Beijing, 100076)
Abstract: The genesis and development of Wavelet Analysis theory is introduced in this paper. The characteristics and application of Wavelet exchange and the Fourier exchange are compared. The standard to choose the best Wavelet bases is studied. Besides,the application of Wavelet analysis In signal processing for Acoustic Emission is described and some deficiencies on wavelet analysis and the tendency in the future is proposed.
Keywords: Acoustic Emission, Wavelet analysis, Fourier analysis, Signal processing

Relationship between Pipe Characteristics and the Exciting Frequency of Longitudinal Guided Waves
WANG Yue-min SHEN Li-hua SHEN Chuan-jun SUN Feng-rui
(College of Ship and Power, Naval University of Engineering. Wuhan. 430033, China)
Abstract: The characteristic of guided waves propagation in pipes that L(0, 1) and L(0, 2) have a cutoff frequency are respectively discussed, and the calculation formulas of their cutoff frequency are given in this paper. The varied relationship between the cutoff frequency of L(0, 1) and L(0, 2) mode guide waves, the outer diameter and wall thickness of pipes are discussed, respectively. For a given steel pipe, experiments are carried out by selection of different exciting frequency. The results show that the “low-pass” type cutoff frequency of L(0, 1) and “high-pass” type cutoff frequency of L(0, 2) are reduced with increasing of outer diameter of pipes, and the “low-pass” type cutoff frequency of L(0, 1) and “high-pass” type cutoff frequency of L(0, 2) are initially increased with increasing of wall thickness of pipes, but the increased amplitude is slowly changed a little. When the outer diameter of pipes is more than a certain value, both of the cutoff frequencies are not changed with varied of wall thickness of pipes. The experimental results are well agreed with theoretical computation of selected exciting frequency for pipes guided waves NDT.
Keywords: Non destructive testing; Magnetostrictive sensor; Guided wave; Dispersion

Signals and Image Characterization of Titanium Thick Welds Based On UPA
WEI Quan1,WU Guan-hua1, WU Wei1,ZHONG De-huang1,2
1. Key laboratory of NDT, Ministry of Education, Nanchang Hangkong University,
Nanchang, 330063, China
2. GE Insp. Tech, Non-US 200233)
Abstract: Ultrasonic Phased Array technology was used to detect defects in titanium welds. The scanning images of some typical defects were analyzed. The results show that combine A scan signals and S-scan images can PA detect effectively in discrimination, sizing and locating. The defect sensitivity and efficiency were superior to those of A scan.
Keywords: Titanium;Thick Welds;Ultrasonic Phased Array;Image Characterization

Research on NDT Inspection and Safety Assessment Methods of Oil & Gas Station Pipeline Defects
Weibin Wang, Muyang Ai, Yuqin Wang, Guichun Liu, Guangwen Liu, Wenqiang Tong, Zhe Liu
(PetroChina Pipeline R & D Center, Langfang, Hebei, 065000)
Abstract: Conventional ultrasonic testing such as thickness gauging uses bulk waves and only tests the region of structure immediately below the transducer. Some new NDT methods have been developed to detect oil & gas pipeline defects. Several kinds of technology such as ultrasonic guided waves, ultrasonic phased array, time of flight diffraction (TOFD), are presented in detail. Safety assessment of station pipeline was made to give advice for repair and rehabilitation. All methods are studied to build an integrated inspection and assessment system of oil and gas station pipelines.
Keywords: Ultrasonic Guided Wave; Phased Array; TOFD; Safety Assessment

Introduction of Non-contact Ultrasonic Test Technique
WU Ben-hua
(Wuxi Branch of Jiangsu Province Special Equipment Safety Supervision Inspection Institute, Wuxi 214174,China)
Abstract: The tradition ultrasonic test uses the contact type transducer. That is, between the ultrasonic probe and the examined materials or components, the ultrasonic coupling medium such as fat or water is used to enable the most energies to import into the work-piece. However when testing the pressure vessel with heat insulator, the machine must be closed down and the heat insulator layer must be removed. Also the vessel’s surface must be polished. These preparation jobs will waste large amount of manpower and resources, and the insulator layer is often very difficult to be restored. These have brought very tremendous influence for our test work, so we must develop the new technique of non-contact ultrasonic test vigorously. In this paper, four test methods which researched more at present is introduced, such as electromagnetic ultrasonic, electrostatic coupling, air coupling and laser ultrasonic.
Keywords: non-contact ultrasonic test; electromagnetic ultrasonic; electrostatic coupling; air coupling; laser ultrasonic

Discussion on In-service Penetrant Testing Procedure for Tianwan Nuclear Power Station
Wu Xin-zhong
(Wuhan Jiufang Engineering Technology Co., Ltd., Wuhan 430077)
Abstract: This article introduced the procedure of inservice penetrant testing for TNPS T101 overhaul, and the effects and limitations of penetrant testing are evaluated.
Keywords: Tianwan Nuclear Power Station (TNPS), penetrant testing (PT) procedure

Experimental Investigation of the Stability of X-Ray Film’s Performance and Developing Process
XIAO Zhi-qiang
(Institute of Fluid Physics, CAEP, Mianyang of Sichuan Prov. 621900, China)
Abstract: X-Ray films had been exposed with sensitometer and then developed in darkroom. By measuring the fluctuation of the relative sensitive curves, the stability of X-ray film’s performance and developing process had been investigated.
Keywords: X-Ray film sensitometer sensitive curve stability

The application of new ultrasonic probes which is at The butt welds of the class short tubes
Xiao Zhongyi Zhang Chunyou
Zhejiang Non-destructive Testing of Inspection Engineering Company
Hangzhou of Zhejiang Province, 310015
Abstract: This text gathers the butt welds of the some power station boiler class short tubes can't adapt to radiographic examination because of the space and time relation. The parts have to adapt ultrasonic inspection, and because of the short tubes length is shorter. The common small diameter tube ultrasonic probes can't satisfy the spot examination. According to the spot of the actual circumstance, a kind of small diameter tube ultrasonic probes is designed to meet the spot actual examination request, thus, insuring the quality of the spot butt welds, and also lower examination cost.
Keywords: ultrasonic inspection, new ultrasonic probes, small diameter tube, application.

Robust H∞ Guaranteed Cost Satisfactory Fault-Tolerant Control for
Discrete-Time Systems with Quadratic D Stabilizability
Xiaodong Han*, Cuimei Bo and Zhiquan Wang
School of Automation, Nanjing University of Science and Technology, Nanjing, Jiangsu Province, China,
*Corresponding author E-mail:
Abstract: The problem of robust H∞ guaranteed cost satisfactory fault-tolerant control with quadratic D stabilizability against actuator failures is investigated for a class of discrete-time systems with value-bounded uncertainties existing in both the state and control input matrices. Based on a more practical and general model of actuator continuous gain failures, taking the transient property, robust behaviour on H∞ performance and quadratic cost performance requirements into consideration, sufficient conditions for the existence of satisfactory fault-tolerant controller are given and the effective design steps with constraints of multiple performance indices are provided. Meanwhile, the consistency of the regional pole index, H∞ norm-bound constraint and cost performance indices is set up for fault-tolerant control. A simulation example shows the effectiveness of the proposed method. Compared with the systems taking no account of failures, the necessity of such a satisfactory fault-tolerant control is proved further.
Keywords: fault-tolerant control; actuator failures; consistency theory; quadratic D stabilizability

Investigation of defects in one dimension by using nonlinear resonance ultrasound spectroscope
Xiaozhou Liu, Wenxin Qu, Xiufen Gong
Key Laboratory of Modern Acoustics, Ministry of Education, Institute of Acoustics,
Nanjing University, Nanjing, 210093, China
Abstract: In this paper, the defects with asymmetry boundary are analyzed by using nonlinear resonance ultrasound spectroscope. The expressions for resonance frequency shift and amplitude of high harmonics induced by classical cubic nonlinearity and non-classical nonlinearity under this boundary condition are given and the numerical simulations are carried to demonstrate that this method can well differentiate the positions of the left or right defects in the bar.
This work is supported by the National Natural Science Foundation of China (No.10674066) and State Key Laboratory of Acoustics.

Analysis of the executive condition about Penetrant testing part of JB/T4730.5
Xing zhaohui
(Jinan Bureau of Quality and Technical Supervision, Jinan, Shandong Province, 250002)
Abstract: In the two years since the publication of the JB/T4730-2005 standard, some items still have not been carried out effectively .Quality control ,standardization of test piece , control of deleterious elements and so on exist gaps in performance and should be highly regarded.
Key words: JB/T4730.5-2005;Penetrant testing; execute; analysis

Pressure Tube Detection Research of Metal Magnetic Technology
XU Wei-pu QIU Yan-li
Shanghai Institute of Special Equipment Inspection and Technical Station, shanghai, 200062
Abstract: Testing principles and practice applications of Metal Magnetic Memory Test (MMT) were introduced in this paper; The stress of pressure tube were analyzed; MMT technology that used in pressure tube detection were also calculated and investigated; Application foregrounds of MMT were argument.
Keywords: Magnetic memory;pressure tube;stress muster

De-noising of the Infrared Image to Defects Based on Wavelet Transform and Median Filter
Xue Li1 Zhu Yongkai1 Wang Haitao1
(1.College of Automation, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China)
Abstract: The wavelet transformation has many advantages, such as the low entropy, the multi-resolution analysis characteristic, de-correlation and flexibility of choosing basis and so on, so it has become an important method for image de-noising. In this paper, the basic principle of wavelet transformation is presented, and we use it to process the infrared image to defects, connecting with the median filtering. Experimental results show that the effect of this method is better than the traditional methods, it could effectively reduce the Gaussian and Impulse noise at the same time, so it can be used for the further analysis and processing of the defects.
Keywords: infrared image; wavelet transformation; median filtering; image denoising

Monitor the circumferential welds of Multi-layer Thick-wall Pressure Vessels Serving at Elevated Temperature by Ultrasonic Testing
Xufeng Li
Guangdong Institute of Special Equipment Inspection
6F Haijing Center, 144-152 Huangpu Avenue Center, Tianhe District, Guangzhou 510655, China
Abstract: Through a series of researches and analyses the feasibility of ultrasonic inspection at high temperature, After some experimentation was carried at laboratory, It was applied on the cyclic welding seam of the multi-layer and thick-wall pressure vessel by using special high temperature probe & couples,And the high performance UT detector and the tip diffraction technology was recommended. Carry one's point of the ultrasonic monitor at high temperature of that equipment in service.
Keywords: Multi-layer and Thick-wall P.V. In service, High Temperature, Ultrasonic Monitoring

A Review of Current Status in Applying Special Radiographic Techniques to Pressure Equipment in China
Yan LI
Jiangsu Taihu Boiler Co., Ltd., Wuxi 214187, China
Abstract: Special radiographic examination(RT) techniques for the common and special welded joints in pressure equipment are outlined, covering the tube-to-tubesheet joints of heat exchangers and the nozzle and branch joints of various vessels for which the examination procedures are more difficult. The characteristics and attention matters of mega-voltage radiography and the main points and difficulties in radioscopic real-time imaging techniques are pointed out. Finally, the state-of-art and future of digital radiography are described.
Keywords: Radiographic examination; Pressure equipment; T-shaped welded joint; Tube-to-tube sheet joint; Nozzle joint; Real-time imaging; Digital radiography

Which should Pay Attentions to in Daily Nondestructive Testing by the Discussion about
Dyeing Machinery Manufacture
YAN Xiao-jun
Abstract: Analyzed the dyeing machinery, NDT request and the concrete implementation measure, proposes some representative factors should to be paid more attentions to during the NDT implementation process, and sums up those needs well done in NDT work for the daily product manufacture besides the concrete examination sequence of operation.
Keywords: Dyeing machine, Nondestructive testing, Consideration factors, Examination quality

A fault diagnosis method based on ICA in industrial processes
YANG Hai-rong, BO Cui-mei, ZHANG Guang-ming
(College of Automation, Nanjing University of Technology, Nanjing 210009)
Abstract: Multivariate statistical process control (MSPC) methods have been widely used in process industries for fault detection. A new process monitoring method based on independent component analysis (ICA) is proposed. The essential independent components are extracted to drive a process and combined with process monitoring techniques. Statistic , and are calculated respectively to detect faults. The proposed monitoring method was applied to Tennessee Eastman (TE) process, which is characterized by a variety of fault sources with non-Gaussian characteristics. The simulation results clearly showed that the fault detected rate and fault detected time of the proposed ICA method are better than ones of PCA monitoring method.
Keywords: Fault diagnosis; Process monitoring; Independent component analysis; TE process

Yang Nengjun, Lei Tao
(The Second Artillery Engineering College, XI’an 710025)
Abstract: The selection of AE source location technique affects the accuracy source location directly. By the testing experiment on LF3 plate, this paper compares traditional threshold-voltage source location technique with the wave-crest technique based-on wavelet-analysis and the cross-correlation technique based-on wavelet-analysis. The adaptive and theoretical analyses of these location techniques, which provides the basis for actual application.
Keywords: Acoustic Emission, Wavelet Analysis, Source Location

EMD and Research Employed to Acoustic Emission Testing
Yang Nengjun, Tang Wei, Long Xianhai, Lei Tao
(The Second Artillery Engineering College, Xi’an 710025)
Abstract: The principle and current research of Empirical Mode Decomposition (EMD) have been introduced in this paper. Based on the advantages and shortages of EMD, it is the first time to use this method to Acoustic Emission Testing. By the theoretical analysis, this paper enumerates several kinds of typical application in Acoustic Emission Testing and provides to consult for applying this method to Acoustic Emission realm.
Keywords: Empirical Mode Decomposition (EMD);Acoustic Emission Testing

Investigation and Application of Total Station Leveling in Settlement Monitoring on a gym
YANG Peng -Yuan
(College of Civil Engineering , Lanzhou Univ. of Tech. , Lanzhou, 730050, China)
Abstract: Applied traditional leveling survey methods to total station height difference survey, simply called total station leveling survey. The methods have flexibility of set station, high precision and rapid process , but also have ability of the restraint of topography to traditional leveling survey ; theoretics and practice indicates that this methods can replace the Ⅲ grade leveling survey , and can also provide the precision of traditional engineering settlement monitoring required.
Keywords: Total station leveling methods;settlement monitoring;error analysis;application

The Simulation and Experimentation Research of Defect Depth by Infrared Thermography
Yang ru-yi1, Tian Yu-peng2, Liang Bing3
(1 and 2 Department of Measuring and Testing Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016 China)
(3. Nanjing Boiler and Pressure Vessel Supervision and Inspection Institute, Nanjing, 210001 China)
Abstract: ANSYS, finite element analysis software, is utilized to analysis the defect models of different size and depth in this paper. Based on the models, the defect depth on polymer material’s surface and the relation between defect depth and time information are analyzed, the concept of initialization separation time and maximum contrast changing time are given, and then compared them with the maximum contrast time. At last, the influence of defect size for defect depth is analyzed, and the simulation results are proved by experimental system, the results show that the deviation of initialization separation time which is utilized to analysis the defect depth information is minimum, namely the most precise.
Keywords: Defect; Finite Element; Infrared Thermography; Temperature Contrast

Research on Ultrasonic Testing Method of Weld in the Trail Tube
(Nanjing Boiler and Pressure Vessel Supervision and Inspection Institute , Nanjing, 210001, China)
Abstract: The article introduced the trail tube weld joint's ultrasonic testing existence's technical difficulty, unifies the JB/T4730-2005 standard, carries on the optimization design to probe head each parameter, through to the field welding attachment in each kind of flaw's analysis and to each kind of known flaw's actual crack detection operation, has obtained some usable experience, enhanced the trail tube ultrasonic testing accuracy and the reliability.
Keywords: Trail tube;ultrasonic crack detection

The Uniform Testing of Metal Matrix Composites with TIRP Method
Yifei Gao 1, Zhenggan Zhou 1*, Fangcheng He 2
1. School of Mechanical Engineering and Automation, Beijing University of Aeronautics and Astronautics, Beijing 100083, P. R. China
2. Department of NDT, Beijing Institute of Aeronautical Materials,
Beijing 100095, P. R. China
Abstract: In order to evaluate the uniform of SiCp reinforced aluminum metal-matrix composites (MMC) fabricated by powder metallurgy, the ultrasonic velocity imaging was carried out with the method of thickness independent reflector plate (TIRP). Ultrasonic velocity in MMC can be used to calculate the stiffness constants and Yang’s modulus, which are influenced by the volume percentage of SiCp. The TIRP method based on pulse-echo mode was developed to measure very small changes in thickness and velocity with a flat and rigid reflector plate behind specimen. Firstly, purpose of ultrasonic velocity imaging of MMC and basic principle of TIRP were introduced. Secondly, an ultrasonic scan system employed to apply TIRP method was described. Thirdly, the experiments’ results of ultrasonic velocity imaging of MMC specimen obtained with TIRP and back surface echo (BSE) respectively were compared and discussed. It is showed that the images generated by TIRP have more details than those by BSE. Finally, the factors affecting accuracy and precision in the implementation were considered which may be used to advance the experiment.
Keywords: ultrasonic velocity imaging, aluminum metal-matrix composites, thickness independent reflector plate (TIRP)

Detection of Surface Breaking on Cylinder Material using Surface Acoustic Wave generated by Scanning Laser Source
Yifei Shi, Jing Xie, Zhonghua Shen, Xiaowu Ni, Jian Lu
(Department of Information Physics and Engineering, School of Science, Nanjing University of Science and Technology, Nanjing 210094, People's Republic of China)
Abstract: A finite element model for laser–generated surface waves on the elastic cylinder material is built according to the thermo-elastic theory, and an experimental installation using laser interferometer as the ultrasonic wave receiver is set up to verify the numerical results. By changing the relative distance between the laser source and the surface notch in the computation, the scanning procedure is simulated. The corresponding varieties of amplitudes of the surface waves, which propagate circumferentially on the cylinder material, are presented and the physical mechanisms are analyzed. The influence of the depth of the surface notch is also discussed. The results demonstrate the SLS technique can be applied to detect tiny crack whose depth is smaller than the wavelength of the SAW.
Keywords: laser ultrasonics; finite element method (FEM); scanning laser source (SLS); Surface acoustic wave (SAW)

Analysis of Sound Ray Theory and FEM for Ultrasonic Propagation in a Finite Rod
Youxing Chen1, Zhaoba Wang1, Jianli Zheng2, Xia Zhao1, Yuan Li1
(1.National Key Laboratory for Electronic Measurement Technology, North University of China, Taiyuan, China)
(2. Shanxi Beifang Xing'an Chemical Industrial Co., Ltd., Taiyuan, China)
Abstract:Aiming at the following echo presented with ultrasonic propagation in a finite metal rod, the sound ray theory is used to analysis wave mode conversion of ultrasonic propagation in a finite rod and the impact on echo by it, and the conclusion is taken that the interval of the echoes are decided by the rod’s diameter and wave velocity. The process of ultrasonic penetrating through a rod and the final ultrasonic echo are analyzed by the FEM. In the practical application, based on the results of the FEM simulation for ultrasonic propagation in rods and the selectivity of the material and dimension, the characteristic echo and following echoes are identified at time domain, aiming to extracting characteristic echo from the ultrasonic signal.
Keywords: FEM, ultrasonic propagation, wave mode conversion, high temperature testing

The Application of Phased Array Inspection Technique in the Truck’s Wheel Hub
YU Bao-hong1,2 SHAO Zhi-hang1,2 LUO Yun-dong1,2
(1. Shanghai Baosteel Industry Inspection Corp., Shanghai, 201900, China;
2. Baosteel-GE Inspection Technical Application Centre, Shanghai 201900, China)
Abstract: According to the invalidity of one truck’s wheel hub, preventable testing was used on the same kinds of reserve wheel hubs. Compared the application with convention ultrasonic and phased array inspection technique, and RT retesting, summarize the advantages of phased array inspection technique.
Keywords: Phased Array Inspection;Wheel Hub;Defect;Image

Research on Inspection and Analysis Methods of Buried Gas Pipeline Using Ultrasonic Guided Waves
Yuqin Wang, Weibin Wang, Muyang Ai, Guichun Liu, Guangwen Liu, Wenqiang Tong, Zhe Liu
(Petrochina Pipeline R & D Center, Langfang, Heibei Province, 065000)
Abstract: Ultrasonic Guided Wave testing is widely used for the inspection of buried pipelines at present. The inspection principle, characteristics and application were introduced. As an example, pipelines in gas station were tested on-site and the testing result reliability was verified by excavation. Data analysis method was developed to analyze the inspection data. Comparison results showed that the ultrasonic guided waves can make it reality to test on site quickly, and has wide prospect.
Keywords: Ultrasonic Guided Wave; Inspection; Buried Pipeline; Corrosion

Flaw Identification of Ultrasonic Signal based on Empirical Mode Decomposition and Optimal Support Vector Machine
ZHAO Xiufen1,YIN Ying2,TIAN Guiyun2,YIN Ying2,YIN Guofu1
(1 College of Manufacturing Science and Engineering, Sichuan University, Chengdu 610065)
(2 School of Electrical, Electronic and Computer Engineering, University of Newcastle, UK)
Abstract:Automatic identification of flaws is very important for ultrasonic nondestructive testing and evaluation of large shafts. A novel automatic identification method of flaws based on empirical mode decomposition (EMD) and optimal support vector machine (SVM) is presented. Firstly, ultrasonic signals are decomposed into a finite number of stationary intrinsic mode functions (IMFs), then the AR mode of each IMF component is established, finally, the auto-regressive parameters and the variance of remnant are regarded as the flaw characteristic vectors and served as input parameter of optimal SVM classifier to ultrasonic signals. The experimental results show that the proposed approach can classify the inner flaws of large shafts accurately and effectively even in the condition of smaller umber of samples.
Keywords:Ultrasonic Testing, Empirical Mode Decomposition, Support Vector Machine, Flaw Identification

Weld Defects Identification Based on Multi-Class Support Vector Machine for X-Ray Inspection Digital Image
Zhao Yaqin1, Zhang Guangming2, Zhao Maocheng1, Tang Guizhong2
1)College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China
2 )School of Automation, Nanjing University of Technology, Nanjing 210009, China
Abstract. It is difficult to classify weld defects of pressure vessel because of complated welding structure and welding line. This paper presents a new weld defects identification scheme for X-ray inspection diginital image. Instead of using artificial neural network, the method recognizes weld defects within X-ray image based on support vector machine(SVM) for pressure vessel. Above all, the edge of one weld defect is detected after X-ray weld image is preprocessed. Afterwards, eight defects features are extracted to construct one feature vector for each defect sample according to its edge figure. Furthermore, recognizing model based on a multi-class SVM is established to classify weld defects by the feature vectors. The results showed the scheme could effectively identify weld defects genres for X-ray inspection digital image.
Keywords: Multi-class SVM, X-ray weld image, image processing, defects identification

Research of Preprocessing of X-ray Digital Radiograph
Zhao Ying-liang, Wang Li-ming, Han Yan
(National Key Laboratory For Electronic Measurement Technology,North University of China, Taiyuan 030051, China)
Abstract: With the further demand to the quality of X ray Digital Radiograph in the industrial CT technique, x-ray automatically inspection and recognition, the traditional methods cannot gratify the need of image preprocessing under the different imaging condition. Aiming at x-ray dispersion and beam-hardening correction, and on the study of the traditional methods, a new preprocessing method was brought forward. The method is independent of the imaging apparatus, and foreign to the material and structure of work-pieces. And it can be applicable for the all ranges of industrial x-ray energy. The method was used in the processing of the simulated and practical images under the influence of dispersion and hardening, and the result showed that it can effectively improve the image and was of universality.
Keywords: industry CT; beam-hardening; polychromatic system parameters; wavelet transform

The method of defect recognition in ultrasonic infrared thermography
Zheng Kai 1, Zhang Shu-yi 2, Zhang Hui 2 and Cai Shi-jie 3
(1.Jiangsu Province Special Equipment Safety Supervision Inspection Institute, Nanjing 210003, China
2. Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093, China
3. Department of Computer Science & Technology, Nanjing University, Nanjing 210093, China )
Abstract: Ultrasonic Infrared Thermography (UIRT) Technology is a novel effective nondestructive testing technique combined with ultrasonic and infrared. Auto-recognition of defects can improve the efficiency of the technique. According to the characteristics of the heat transfer at the defect presented in this paper, a method is used to find the signals of defects. A series of UIRT images as an instance is processed, and the results illustrates that the method is effective.
Keywords: Ultrasonic Infrared Thermography, Recognition of defects, Signal processing, NDT

The discussion in X shoots the field of lines interior the mutually perpendicular uniform thickness steel plate transmission
Zhou Guo Yi
The Jiangsu Province special equipment safety surveillance examines the research institute Taizhou Branch Taixing institute, Jiangsu Taixing, 225400
Abstract: The portal type hoist crane box beam is an important stress part. On the lap withstanding tensile stress load, specially both sides column's upside, takes the responsibility stands under load Holland's car when walks from an end to another end, this spot receives the stress unceasingly to change, in this spot welded joint's flaw will expand in the use process. The box beam selects the steel plate thickness to be thin generally, in uses in the hoist crane examination, strengthens the box beam non-destructive inspection spot-check beam examination to be very particularly essential. The box beam external dimensions are big and are away from the ground to be high, carries on the dog-legged single shade beam crack detection from the opposite side, the focal distance is long, and is not easy to operate. This article unifies on a portal type hoist crane box beam lap's inclined X-ray dog-legged single shade crack detection, analyzed X has shot in the field of lines the mutually perpendicular two uniform thickness steel plate transmission.
Keywords: X shoots the field of lines, Vertical, Box beam, Uniform thickness steel plate

The Investigation And Analysis Of Intermittent Linear Shadow Image In X-ray Films For SS.(stainless steel) Welds.
Zhu Chang Hong
Jiangsu Province Special Equipment Safety Supervision and Inspection Institute Zhenjiang Branch (division) 212300
Abstract: Austenitic stainless steel welding technology, un-successive stripe shadows of welding on X-ray film cutting the welding blot with high-temperature blowing gas by carbon-arc welder molding fixture welding quality

Research on Segmentation Method for Testing Images of X-ray Security Inspection Systems
Zhu Guä, Wei Wuà, Yifei Gaoä, Dong Weiä, Zhenggan Zhouäù
ä School of Mecha. Eng. & Auto., Beijing University of Aeronautics and Astronautics, Beijing 100083
à Center of Aviation Safety Technology, Civil Aviation Administration of China, Beijing 100028
ù Correspondence Author
Abstract: The segmentation for the image of different test items is the foundation of quality assessing for testing image which is generated by X-ray security inspection systems. The segmentation method mentioned in this paper is based on HSI (Hue, Saturation, Lightness) color space, use polygon approximation to accomplished image edge extraction, segment image depending on geometric features. The experiment results show that it can accomplish segmentation for the low quality image with large noise and distortion.
Keywords: HSI color space; Polygon approximation; Image segmentation

Study for magnetostrictive guided wave signal identification based on Duffing chaotic oscillators
Zou Jun, Wu Xinjun, Xu Jiang, Kang Yihua
(School of Mechanical Science & Engineering, Huazhong University of Science and Technology, Wuhan, 430074 China)
Abstract: The technology of magnetostrictive generated guided waves has been applied to nondestructive testing (NDT) widely. It is difficult to detect the small flaw signal because of guided wave’s dispersion and multimode. According to these characters of the signal, the method based on Duffing chaotic oscillator is presented to detect flaw signal. First, the Duffing chaotic oscillator is set into the periodic state. Then, the signal without pulsed electromagnetic is introduced into Duffing system, and the system is into the same state whether the signal with or without flaw. When the signal with the pulsed electromagnetic is introduced into system, the system will still in periodic state if it doesn’t include flaw signal. However, if it includes flaw signal, the system will change into chaotic state. Therefore, this method can be employed to identify the small flaw and improves the accuracy of fault detection.
Keywords: Duffing chaotic oscillators, guided wave, signal processing, nondestructive testing