Non-destructive testing of weld defects based on finite element analysis of magneto-optical images

2020 ◽  
Author(s):  
Congyi Wang ◽  
Huimin Zeng ◽  
Yanxi Zhang ◽  
Yaowu Song ◽  
Deyong You ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Element Analysis ◽  
Weld Defects ◽  
Optical Images ◽  
Non Destructive

Evaluation of near-drum thinning data in recovery boiler generating bank tubes

TAPPI Journal ◽  
2016 ◽  
Vol 15 (7) ◽  
pp. 491-500
Author(s):  
W.B.A. SANDY SHARP ◽  
W.A. BILLY JONES
Keyword(s):  
Finite Element Analysis ◽  
Thickness Measurement ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Element Analysis ◽  
Data Set ◽  
Industry Standard ◽  
Recovery Boiler ◽  
Thickness Measurements ◽  
Non Destructive

Near-drum thinning affects the fireside surface of recovery boiler generating bank tubes near the surface of the mud drum. Although sophisticated thickness scanning equipment has been developed to rapidly make tens of thousands of thickness measurements in the portion of a tube that is vulnerable to near-drum thinning, methods for using these data to evaluate fitness-for-service have not shown similar advances. Non-destructive testing companies typically use a technician’s subjective judgment to identify the “thinnest reliable" thickness measurement on each tube. Some mills decide whether tubes can continue in operation or should be plugged or replaced based on this single thickness measurement. However, finite element analysis of the remaining strength of individual tubes thinned in the near-drum area suggests that it is essentially impossible to identify the weakest tubes from simple empirical rules. In the absence of an industry standard for evaluating these data, different mills could reach different conclusions about the fitness-for-service of a tube from the same data set. This paper reviews the technology for scanning the thickness of generating bank tubes and discusses approaches that have been used to identify the tubes most weakened by near-drum thinning and to evaluate the fitness-for-service of individual tubes.

Design of controllable units for mechanical transmissions

2021 ◽  
pp. 22-26
Author(s):  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Simulation Modeling ◽  
Mechanical Transmission ◽  
Non Destructive Testing ◽  
The Finite Element Method ◽  
Destructive Testing ◽  
Bench Tests ◽  
Non Destructive ◽  
Element Method

The scientific and methodological foundations of the design of mechanical transmission units of transport and technological machines, adapted for diagnosing the operability by thermometry parameters, based on the results of bench tests and simulation modeling by the finite element method, are considered. An algorithm is developed for the design testing of power units for adaptability to thermometric non-destructive testing. Keywords: design, controllability, diagnostics, thermometry, finite element method [email protected]

Non-Destructive Detection of GIS Aluminum Alloy Shell Weld Based on Oblique Incidence Full Focus Method

2020 ◽  
Vol 1007 ◽  
pp. 105-110
Author(s):  
Xin Xin Wang ◽  
Cheng He ◽  
Pu Zhi Zhao ◽  
Yi Zheng ◽  
Shi Hao Jiang ◽  
...  
Keyword(s):  
Oblique Incidence ◽  
Near Field ◽  
Calibration Coefficient ◽  
Quantitative Detection ◽  
Imaging Method ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Field Range ◽  
Weld Defects ◽  
Non Destructive

In this paper, a new ultrasonic phased array full focus imaging method based on oblique incidence is proposed to solve the problem of the non-destructive testing of the internal defects in the GIS (gas insulated switchgear) shell welds. By using wedge coupling, the measured weld is far away from the near-field range of the transducer, and the detection angle range can be increased by changing the propagation direction of the acoustic beam. Based on Snell's law, the propagation characteristics of the ultrasonic wave in the interface are studied. On the basis of the conventional ultrasonic array matrix and the full focus imaging algorithm, by introducing the energy attenuation calibration coefficient of the acoustic wave propagation through the wedge, the correction amplitude of the specific focus point p(x, z) is obtained, The non-destructive testing of weld defects of GIS shell in the spot is carried out, and the test results show that the qualitative and quantitative detection of the weld defects can be well realized by using this method.

scholarly journals Long-Term Performance of Trestle Bridges: Case Study of an Indonesian Marine Port Structure

2020 ◽  
Vol 8 (5) ◽  
pp. 358 ◽  
Author(s):  
Yusak Oktavianus ◽  
Massoud Sofi ◽  
Elisa Lumantarna ◽  
Gideon Kusuma ◽  
Colin Duffield
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Service Life ◽  
Field Measurement ◽  
Field Measurements ◽  
Element Analysis ◽  
Moment Capacity ◽  
Non Destructive

A precast reinforced concrete (RC) T-beam located in seaport Terminal Peti Kemas (TPS) Surabaya built in 1984 is used as a case study to test the accuracy of non-destructive test techniques against more traditional bridge evaluation tools. This bridge is mainly used to connect the berth in Lamong gulf and the port in Java Island for the logistic purposes. The bridge was retrofitted 26 years into its life by adding two strips of carbon fiber reinforced polymer (CFRP) due to excessive cracks observed in the beams. Non-destructive field measurements were compared against a detailed finite element analysis of the structure to predict the performance of the girder in terms of deflection and moment capacity before and after the retrofitting work. The analysis was also used to predict the long-term deflections of the structure due to creep, crack distribution, and the ultimate moment capacity of the individual girder. Moreover, the finite element analysis was used to predict the deflection behavior of the overall bridge due to vehicle loading. Good agreement was obtained between the field measurement and the analytical study. A new service life of the structure considering the corrosion and new vehicle demand is carried out based on field measurement using non-destructive testing. Not only are the specific results beneficial for the Indonesian port authority as the stakeholder to manage this structure, but the approach detailed also paves the way for more efficient evaluation of bridges more generally over their service life.

Rapid Defect Reconstruction Based on Genetic Algorithm and Similar Model in Remote Field Eddy Current Non-Destructive Testing

2014 ◽  
Vol 518 ◽  
pp. 269-274 ◽  
Author(s):  
Xiao Jie Xu ◽  
Wen Lin Pei
Keyword(s):  
Genetic Algorithm ◽  
Finite Element ◽  
Eddy Current ◽  
Non Destructive Testing ◽  
Similar Model ◽  
Destructive Testing ◽  
Defect Reconstruction ◽  
Element Computation ◽  
Non Destructive ◽  
Finite Element Computation

Defect reconstruction of remote field eddy current belonged to electromagnetic inverse problem in materia Non-Destructive Testing. In view of disadvantages in present defect reconstruction methods, such as over-long time or excessive need for training samples, a new defect reconstruction method based on similar model and genetic algorithm was investigated as follows: similar model between non-axisymetric defect and axisymetric defect was represented, and proportionality factor was deduced by skin depth equation. As a result, the time-consuming forward problem solution in defect reconstruction, which using 3D finite element computation conventionally, was simplified to 2D finite element computation. At the same time, a method designed to accelerate convergence of genetic algorithm was adopted, and more times saving were obtained. Computation results show that, total defect reconstruction time is reduced to 7.6%, compared with directly 3D finite elemet computation, while reconstruction accuracy remains almost the same.

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