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[en] Various tubular objects are utilized for strategic and critical applications in nuclear, aviation, space and petrochemical industries. Major tubular objects employed in these industries are tubes, pipes and vessels which are inspected for planar and volumetric defects hidden inside the material. Various Non-Destructive Testing (NDT) techniques are used for the inspection of such circular objects both during fabrication as well as during in-service stages. Non-Destructive Evaluation (NDE) of these components is carried out in conformance with various codes and standards such as ASME, ASTM and IIW etc. Ultrasonic Testing (UT) is a well-known NDT technique to perform flaw detection, sizing and characterization of tubular objects. Other than the accurate measurement of loss of wall thickness, measurement of variation in Inner Diameter (ID) and Outer Diameter (OD) is also an important requirements of tubes and pipes. Ultrasonic imaging systems are utilized for volumetric inspection of the desired region of tubes and pipes. Imaging systems provide both the gauging and imaging operations. Such a high-speed generic system capable of both, B/C-Scan imaging and high resolution gauging of tubes and pipes, is the requirement of critical applications. Ultrasonic Testing (UT) method, currently used for tube inspection, is not always adequate for flaw characterization. Utilities occasionally experience problems trying to characterize a flaw (particularly, crack or an off-axis flaw) and define its shape, orientation and size. Typically, the Normal Beam (NB) longitudinal waves and angle beam shear waves employing the Pulse-Echo (PE) or Pitch-Catch (PC) technique are used for tube/pipe testing to detect, characterize and size the flaws located within the tube wall or on the ID region or the OD region of tube/ pipe. (author)
[en] A non-destructive and noninvasive technique is preferable for characterization of the spent fuel solutions in the reprocessing plants, especially samples associated with high radiation dose. A hybrid K-edge/KXRF densitometer (HKED) technique has been designed, fabricated, and commissioned indigenously to accomplish the above objective for the spent fuel solutions from compact reprocessing facility for advanced fuels in lead cells (CORAL), Kalpakkam. This paper describes the customized design, development, calibration and validation of the HKED technique using a series of uranium solutions and corroborating the results with potentiometric method. Further, the pure and mixture of thorium and uranium as well as uranium and plutonium solutions were also assayed by HKED technique. (author)
[en] Segmented Gamma Scanner (SGS) is a commonly used nondestructive testing (Non-Destructive Assay NDA) method. SGS uses radial rotation, axial segmentation, segmented scanning of the non-uniform sample of the "homogenization", making it possible to accurately measure the radioactivity on each segment and is currently widely used in the field of arms control. This paper introduces a self-designed SGS measuring device and uses this device to perform a large number of sub-scanning experiments on different measurement objects in the laboratory. It also studied the detection performance, stability and SGS method of different objects the accuracy of the measurement results.
[en] In this study, 3D shape measurement and path design methods for automatic nondestructive testing were investigated. A rotation was added to the 2D shape measurement sensor, and the point cloud data obtained from the measurements was visualized using a mesh generated in MATLAB. The visualized data was re-meshed to generate inspection points and inspection directions to produce a uniform mesh size. The inspection path obtained using the calculated data is zigzag in shape, since this path was inefficient, optimization was performed. The optimization method aims to minimize the path by maintaining the inspection direction and aligning the inspection position to the same height, thereby eliminating the problem of continuous shaking. Through this study, we have confirmed the possibility of automated, non-destructive inspection systems using shape information
[en] The potential of new non-destructive and diagnostic methods is demonstrated on laser scanning examination of the main reactor flange at the Dukovany-1 reactor (specifically the grooves and the sealing planes). The measurement was performed in order to determine the current condition of this subcomponent and to increase the accuracy of the FEM modules. (P.A.)
[en] The aim of this study was to verify the precision and applicability of two methods of age estimation, Kvaal's and Cameriere's methods, among Brazilian adults. A sample composed of periapical radiographs of canine teeth belonging to 320 Brazilian adults was analyzed, divided into groups according to sex (male and female) and age group (20-29 years, 30-39 years, 40-49 years and 50-59 years). Kvaal's method presented better results when compared to the results of Cameriere's method in the general evaluation of each canine tooth, except for the upper left canine (tooth 23), which presented a mean error (ME) with no statistically significant difference between the methods (Kvaal: ME = 7.43, p = 0.4991, Cameriere: ME = 7.55, p = 0.6982). In the evaluation by age groups, Kvaal's method presented a lower variation between the real age and estimated age when applied to the age groups of 20-29 years and 30-39 years compared to the results provided by Cameriere's method. With respect to the groups aged 40 to 49 years and 50 to 59 years, Cameriere's method presented better performance than the results provided by Kvaal's method. The methods of estimating age proposed by Kvaal and Cameriere are simple and nondestructive and have demonstrated reproducibility and reliability. The Kvaal method was more accurate for the age groups of 20-29 and 30-39 years, and for those over 40 years, the Cameriere method was the most accurate. (author)
[en] In the present study, the partial loss and distortion of turbine blades were acoustically detected while the turbine was rotating. An ultrasonic signal of a specific frequency (300 kHz) was transmitted in the form of continuous sine waves to the rotating turbine model. The signal was reflected on the turbine blade and received by a receiver. The amplitude of the given frequency component in the received signal was analyzed by signal processing. Because ultrasounds are attenuated easily when propagated into air and have a straight characteristic like light, the characteristics of the signals were examined by a quantitative test. The signal attenuation with respect to distance and the signal reduction by eccentricity were observed and compared with the experimental results. Partial loss decreased the sound reflection area; thus, the signal amplitude was reduced. The signal amplitude was inversely proportional to the size of the defect. Distortion caused larger eccentricity between the transmitter and the receiver. Weaker signals were detected with the more distorted blade. When the blade was distorted by more than 20 dg, the amplitude of the signal decreased significantly. In short, defects of turbine blades cause a reduction in the acoustic signal. It was verified that acoustic diagnosis can be applied to detect the partial loss and distortion of turbine blades.
[en] Forensic is an area of law enforcement that relies on many different form of technology to help technician collect evidence that will help solve crime. One of the most innovative uses of technology is Ground Penetrating Radar (GPR) which is a non –destructive testing with high resolution electromagnetic techniques that provide non-invasive site investigation. Therefore, the context of potential buried evidence is secured and preserved. Considered one of the most effective tools, it has being used in various types of cases for example forensic grave detection, military tunnel and landmines detection also weapon detection. (author)
[en] In this paper we present a study on the mechanical properties of nanodiamond enhanced tungsten strengthened aluminium alloy 7075, stored for 28 months under different conditions. One of the samples was stored in terrestrial conditions and the other sample was mounted on the outside of the International Space Station for the same period. The purpose of the experiment is to determine tensile strength, Young’s modulus and Poisson's ratio using different testing procedures and to compare the results with those obtained using the ultrasonic volumetric method Key words: aluminium and alloys, nanodiamond, ultrasonic volumetric method, tensile strength, outer space structures
[en] The National Institutes for Quantum and Radiological Science and Technology (QST) is responsible for manufacturing nine ITER TF coil winding packs (WPs). QST has been proceeding WP manufacturing, the procedure for which has been developed through qualification trials and the authors' experiences. However, since the WP is a huge superconducting coil that has never been fabricated so far, technical challenges newly arose when manufacturing the first WP, such as tight WP dimension tolerance, current center line (CCL) position control and non-destructive examination (NDE) for joint performance. In addition, unexpected discharge happened at instrumentation wires going through the ground insulation layer after the WP cold test. The authors resolved these problems by clarifying the root causes and developing new techniques through additional qualification trials. As a result, WP fabrication is now in the series production phase. In fact, six WPs have been fabricated and manufacturing of the remaining three WPs is on-going. (author)