The Quantification Research of Engine Body Defect that Tested by Ultrasonic Phased Array

2014 ◽  
Vol 494-495 ◽  
pp. 73-77
Author(s):  
Ding Bang Ma
Keyword(s):  
Nondestructive Testing ◽  
Phased Array ◽  
Fatigue Cracks ◽  
The Body ◽  
Testing Equipment ◽  
Ultrasonic Nondestructive Testing ◽  
Long Run ◽  
Ultrasonic Phased Array ◽  
Ultrasonic Emission ◽  
Array Detection

After a long run, the places of body cooperate with valve very easy to produce fatigue cracks. This cracks if not detected, extremely easy to have the accident. As the most commonly used testing equipment, ultrasonic nondestructive testing is often used to detect the engine body. However, most of the existing ultrasonic nondestructive testing equipment is used to detect whether there is a defect, there is little research the specific size of defects. According to the principle of ultrasonic emission, theoretical calculation and combined with test block, get the body phased array detection method.

Production of Realistic Flaws and Their Meaning for Ultrasonic Testing

2019 ◽  
Vol 5 (3) ◽  
Author(s):  
Jiri Hodac ◽  
Pavel Mares ◽  
Jaromir Janousek ◽  
Martin Linhart
Keyword(s):  
Staff Training ◽  
Ultrasonic Testing ◽  
Phased Array ◽  
Fatigue Cracks ◽  
Ultrasonic Test ◽  
P 75 ◽  
Array Technology ◽  
Ultrasonic Echo ◽  
Ultrasonic Phased Array ◽  
Test Result

This work is designed to artificially create test specimens with flaws that behave the same way as real-function flaws when observed by nondestructive testing (NDT) technologies. Thus, the understanding of the detection limitations of NDT methods is needed. In this study, real, realistic, and artificial flaws were compared by ultrasonic phased array technology. Fatigue flaws, which belong to the most common structural issues (Ruzicka, M., Hanke, M., and Rost, M., 1987, Dynamicka Pevnost a Zivotnost, CVUT, Prague, Czech Republic, p. 75), are investigated. Measurements have revealed significant differences in the amplitude of ultrasonic echo from fatigue cracks in distinct phases of crack propagation. Studied specimens with realistic flaws have demonstrated their quality for calibration, staff training, and NDT system qualification. More realistic test specimens will increase ultrasonic test result reliability.

Application of Ultrasonic Phased Array Techniques for Inspection of Stud Bolts in Nuclear Power Plants

2006 ◽  
Vol 110 ◽  
pp. 97-104 ◽  
Author(s):  
Sang Woo Choi ◽  
Joon Hyun Lee
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Phased Array ◽  
Nuclear Reactor ◽  
Fatigue Cracks ◽  
Ultrasonic Inspection ◽  
Phased Array Techniques ◽  
Ultrasonic Phased Array ◽  
Ultrasonic Images

The reactor vessel body and closure head are fastened with the stud bolt that is one of crucial parts for safety of the reactor vessels in nuclear power plants. It is reported that the stud bolt is often experienced by fatigue cracks initiated at threads. Stud bolts are inspected by the ultrasonic technique during the overhaul periodically for the prevention of failure which leads to radioactive leakage from the nuclear reactor. The conventional ultrasonic inspection for stud bolts was mainly conducted by reflected echo method based on shadow effect. However, in this technique, there were numerous spurious signals reflected from every oblique surfaces of the thread. In this study, ultrasonic phased array technique was applied to investigate detectability of flaws in stud bolts and characteristics of ultrasonic images corresponding to different scanning methods, that is, sector and linear scan. For this purpose, simplified stud bolt specimens with artificial defects of various depths were prepared.

Improved Imaging of Fatigue Crack Profile in Thick Cruciform Samples Using Ultrasonic Phased Array Models

2009 ◽  
Vol 132 (1) ◽  
Author(s):  
S. Alavudeen ◽  
C. V. Krishnamurthy ◽  
Krishnan Balasubramaniam ◽  
D. M. Pugazhendhi ◽  
G. Raghava ◽  
...  
Keyword(s):  
Phased Array ◽  
Fatigue Cracks ◽  
Crack Depth ◽  
Potential Drop ◽  
Subzero Temperature ◽  
Virtual Experiments ◽  
Physical Measurements ◽  
Ultrasonic Phased Array ◽  
Experimental Trials

The determination of depth profile of vertical fatigue cracks generated in thick cruciform samples using an ultrasonic phased array is investigated in this paper. The cracks were formed by conducting fatigue fracture test on two mild steel cruciform specimens of 135 mm thickness: one under room temperature and the other under subzero temperature (−70°C). A semi-elliptical surface starter notch of 2 mm width and more than 400 mm length was initially created in the specimens. Alternating current potential drop technique and phased array ultrasonic technique were attempted in order to determine the depth profiles of the starter notch as well as that of the crack. Virtual experiments carried out with a finite-difference time domain based numerical model were found to be advantageous in reducing actual experimental trials, facilitate an understanding of the echo signatures, and help assess the crack depth. The profiles of the crack and the notch were verified through destructive assay of the samples and subsequent dye penetrant assisted physical measurements.

scholarly journals Application of Neuro-Wavelet Algorithm in Ultrasonic-Phased Array Nondestructive Testing of Polyethylene Pipelines

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Reza Bohlouli ◽  
Babak Rostami ◽  
Jafar Keighobadi
Keyword(s):  
Image Processing ◽  
Nondestructive Testing ◽  
Digital Image Processing ◽  
Digital Image ◽  
Phased Array ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Image Processing Techniques ◽  
Ultrasonic Phased Array ◽  
Processing Techniques

Polyethylene (PE) pipelines with electrofusion (EF) joining is an essential method of transportation of gas energy. EF joints are weak points for leakage and therefore, Nondestructive testing (NDT) methods including ultrasonic array technology are necessary. This paper presents a practical NDT method of fusion joints of polyethylene piping using intelligent ultrasonic image processing techniques. In the proposed method, to detect the defects of electrofusion joints, the NDT is applied based on an ANN-Wavelet method as a digital image processing technique. The proposed approach includes four steps. First an ultrasonic-phased array technique is used to provide real time images of high resolution. In the second step, the images are preprocessed by digital image processing techniques for noise reduction and detection of ROI (Region of Interest). Furthermore, to make more improvement on the images, mathematical morphology techniques such as dilation and erosion are applied. In the 3rd step, a wavelet transform is used to develop a feature vector containing 3-dimensional information on various types of defects. In the final step, all the feature vectors are classified through a backpropagation-based ANN algorithm. The obtained results show that the proposed algorithms are highly reliable and also precise for NDT monitoring.

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