scholarly journals Traditional Eddy Current–Pulsed Eddy Current Fusion Diagnostic Technique for Multiple Micro-Cracks in Metals

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2909 ◽  
Author(s):  
Zhenwei Wang ◽  
Yating Yu
Keyword(s):  
Eddy Current ◽  
Health Monitoring ◽  
Diagnostic Technique ◽  
Working Environment ◽  
Quantitative Detection ◽  
Safe Operation ◽  
Metal Structures ◽  
Pulsed Eddy Current ◽  
Micro Cracks ◽  
Oil Gas

Due to a harsh working environment, micro-cracks in metal structures (e.g., airplane, oil/gas pipeline, hydro-turbine) often lead to serious accidents, so health monitoring of the metals is of great significance to ensure their safe operation. However, it is hard to perform quantitative detection of multiple micro-cracks by a single nondestructive testing (NDT) technique because of their limits. To monitor for multiple micro-cracks in metals, a Traditional Eddy Current (TEC) and Pulsed Eddy Current (PEC) fusion NDT technique is proposed in this paper. In the proposed technique, the TEC technique is adopted to seek the locations of the micro-cracks in the whole of the metal, while the PEC technique is adopted to acquire information on the depth of micro-cracks automatically according to the location information by the TEC. The experiments indicate that the TEC–PEC fusion NDT system can localize the micro-cracks as well as detect the micro-cracks quantitatively and automatically; therefore, it can be applied in structural health monitoring of metal equipment or in picking candidate components in re-manufacturing engineering.

scholarly journals An Improved Feature Parameter Extraction Algorithm of Composite Detection Method Based on the Fusion Theory

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Zhou Ying ◽  
Jin Heli ◽  
Liu Banteng ◽  
Chen Yourong
Keyword(s):  
Eddy Current ◽  
Dispersion Model ◽  
Parameter Extraction ◽  
Quantitative Detection ◽  
Differential Signal ◽  
Feature Parameters ◽  
Pulsed Eddy Current ◽  
Extraction Algorithm ◽  
Feature Parameter ◽  
Subsurface Defects

An improved feature parameter extraction algorithm is proposed in this study to solve the problem of quantitative detection of subsurface defects. Firstly, the common feature parameters from the differential signal of pulsed eddy current and ultrasonic are extracted in time domain and frequency domain. Then, the dispersion model and ReliefF model are established to determine the weights of each parameter. Finally, the weights from the two different algorithms are fused by the D-S evidence theory to determine feature parameters. Compared with the PCA feature parameter algorithm from the pulsed eddy current or ultrasonic, the experiment results show the feature parameters extracted by the algorithm proposed in this paper are more effective in quantitative detection of subsurface defects. It will lead to high accuracy in the subsurface defections.

Analysis of field uniformity and quantitative evaluation of subsurface pitting corrosion in conductors via GPEC

2020 ◽  
Vol 64 (1-4) ◽  
pp. 19-29
Author(s):  
Shuting Ren ◽  
Yong Li ◽  
Bei Yan ◽  
Jinhua Hu ◽  
Ilham Mukriz Zainal Abidin ◽  
...  
Keyword(s):  
Quantitative Evaluation ◽  
Eddy Current ◽  
Pitting Corrosion ◽  
Gradient Field ◽  
Uniform Field ◽  
Eddy Current Method ◽  
Optimal Position ◽  
Pulsed Eddy Current ◽  
Field Uniformity ◽  
Processing Algorithms

Structures of nonmagnetic materials are broadly used in engineering fields such as aerospace, energy, etc. Due to corrosive and hostile environments, they are vulnerable to the Subsurface Pitting Corrosion (SPC) leading to structural failure. Therefore, it is imperative to conduct periodical inspection and comprehensive evaluation of SPC using reliable nondestructive evaluation techniques. Extended from the conventional Pulsed eddy current method (PEC), Gradient-field Pulsed Eddy Current technique (GPEC) has been proposed and found to be advantageous over PEC in terms of enhanced inspection sensitivity and accuracy in evaluation and imaging of subsurface defects in nonmagnetic conductors. In this paper two GPEC probes for uniform field excitation are intensively analyzed and compared. Their capabilities in SPC evaluation and imaging are explored through simulations and experiments. The optimal position for deployment of the magnetic field sensor is determined by scrutinizing the field uniformity and inspection sensitivity to SPC based on finite element simulations. After the optimal probe structure is chosen, quantitative evaluation and imaging of SPC are investigated. Signal/image processing algorithms for SPC evaluation are proposed. Through simulations and experiments, it has been found that the T-shaped probe together with the proposed processing algorithms is advantageous and preferable for profile recognition and depth evaluation of SPC.

Real-time wavelet denoising for pulsed eddy current signal based on heterogeneous dual-core

2013 ◽  
Vol 33 (3) ◽  
pp. 866-870
Author(s):  
Xuanbing QIU ◽  
Jilin WEI ◽  
Xiaochao CUI ◽  
Chunhua XIA
Keyword(s):  
Real Time ◽  
Eddy Current ◽  
Wavelet Denoising ◽  
Current Signal ◽  
Pulsed Eddy Current ◽  
Dual Core

Corrosion of Welded Metal Structures of Mining Equipment

2018 ◽  
Vol 69 (9) ◽  
pp. 2563-2566
Author(s):  
Dan Dobrota
Keyword(s):  
Carbon Concentration ◽  
Welded Joints ◽  
Construction Material ◽  
Working Environment ◽  
Mining Equipment ◽  
Metal Structures ◽  
Corrosion Phenomenon ◽  
Welding Regime ◽  
New Material ◽  
Initial Research

Mining equipment made of welded metal structures is strongly affected by the corrosion phenomenon due to the working conditions. Initial research has shown that the corrosion phenomenon is most pronounced in the area of cross-welded joints and welded T-shaped joints. In the researches, there was made a chemical analysis of the welded construction material used respectively of the new material and it was observed a reduction in carbon concentration in the material used, but also a substantial increase in the sulfur concentration compared to the new material. The pronounced corrosion of the metallic structure is influenced by the chemical composition change because the sulfur is a grafitizing and weakening element, and the decrease in carbon concentration causes a decrease in corrosion resistance. Also, the pronounced corrosion is due to the action of sulfurous acid (H2SO3) and hydrogen sulfide (H2S), elements that are present in the working environment of welded constructions. In order to achieve a reduction in the corrosion phenomenon, it is very important that the welded joints are made using the optimal parameters of the welding regime so as to obtain metallographic structure with finer granulations.

Steel Corrosion Characterization Using Pulsed Eddy Current Systems

2012 ◽  
Vol 12 (6) ◽  
pp. 2113-2120 ◽  
Author(s):  
Yunze He ◽  
Guiyun Tian ◽  
Hong Zhang ◽  
Mohammed Alamin ◽  
Anthony Simm ◽  
...  
Keyword(s):  
Eddy Current ◽  
Steel Corrosion ◽  
Pulsed Eddy Current ◽  
Current Systems
Sign in / Sign up

Export Citation Format

Share Document