M. E. Bajgholi, M. Viens, Gilles Rousseau, E. Ginzel, Denis Thibault, Martin Gagnon
Given the significance of minimizing energy production costs, ensuring continuous operation of power generation machinery is imperative. Hydro-Québec, a leading entity in power generation, employs predictive models to forecast the service life of its turbine runners to circumvent unplanned shutdowns. The reliability of these models heavily depends on accurately characterizing runner flaws, which constitutes a critical input. This necessitates the application of non-destructive testing (NDT) techniques for flaw characterization hence the need to evaluate the effectiveness of such methods and explore alternatives that could yield superior diagnostic results. This study aims to evaluate the efficacy of NDT methods especially ultrasonic techniques providing dependable flaw data (both experimental and simulation) to feed life and structural reliability estimation models. By refining the accuracy of these estimates, Hydro-Québec intends to reduce downtime, thereby lowering the costs associated with power generation. Despite considerable research in this domain, a gap remains in our understanding of flaw detectability, particularly in the welded joints of hydroelectric turbine runner blades. This extended investigation not only contributes to the advancement of predictive maintenance strategies but also supports operational efficiency and cost reduction in energy production.
{"title":"Ultrasonic Testing Techniques for Integrity Assessment of Hydraulic Turbine Runner","authors":"M. E. Bajgholi, M. Viens, Gilles Rousseau, E. Ginzel, Denis Thibault, Martin Gagnon","doi":"10.58286/29989","DOIUrl":"https://doi.org/10.58286/29989","url":null,"abstract":"\u0000Given the significance of minimizing energy production costs, ensuring continuous operation of power generation \u0000\u0000machinery is imperative. Hydro-Québec, a leading entity in power generation, employs predictive models to forecast \u0000\u0000the service life of its turbine runners to circumvent unplanned shutdowns. The reliability of these models heavily \u0000\u0000depends on accurately characterizing runner flaws, which constitutes a critical input. This necessitates the application \u0000\u0000of non-destructive testing (NDT) techniques for flaw characterization hence the need to evaluate the effectiveness of \u0000\u0000such methods and explore alternatives that could yield superior diagnostic results. This study aims to evaluate the \u0000\u0000efficacy of NDT methods especially ultrasonic techniques providing dependable flaw data (both experimental and \u0000\u0000simulation) to feed life and structural reliability estimation models. By refining the accuracy of these estimates, Hydro-Québec intends to reduce downtime, thereby lowering the costs associated with power generation. Despite \u0000\u0000considerable research in this domain, a gap remains in our understanding of flaw detectability, particularly in the \u0000\u0000welded joints of hydroelectric turbine runner blades. This extended investigation not only contributes to the \u0000\u0000advancement of predictive maintenance strategies but also supports operational efficiency and cost reduction in energy \u0000\u0000production.\u0000\u0000\u0000","PeriodicalId":495540,"journal":{"name":"Research and Review Journal of Nondestructive Testing","volume":"1976 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141707323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The first Non-destructive testing (NDT) method which evolved in the industrial age was radiographic testing (RT) [1]. Among all NDT methods, RT is no exception, so there are still many issues for optimizations even today. One of them is the measurement of the focal spot of X-ray tubes [2]. The size of the focal spot is critical for imaging, because it determines the spatial resolution in the X-ray image. The classical way to evaluate focal spots of X-ray tubes is by pinhole imaging using a camera obscura [1]. But this method has a natural lower limit, which is defined by the diameter of the pinhole used (today min. 10 µm) [2]. Therefore, focal spot sizes lower than 50 µm diameter cannot be imaged and measured correctly. An alternative approach, which permits this, was investigated here using the edge unsharpness of holes much larger than the focal spot size. The results of both methods were compared using 3 different X-ray tubes.
在工业时代发展起来的第一种无损检测(NDT)方法是射线检测(RT)[1]。在所有无损检测方法中,RT 也不例外,因此直到今天仍有许多需要优化的问题。其中之一就是 X 射线管焦点的测量[2]。焦斑的大小对成像至关重要,因为它决定了 X 射线图像的空间分辨率。评估 X 射线管焦斑的经典方法是使用暗箱照相机进行针孔成像 [1]。但这种方法有一个天然的下限,即所使用针孔的直径(目前最小为 10 微米)[2]。因此,直径小于 50 微米的焦斑无法成像和正确测量。这里研究了另一种方法,即利用比焦斑尺寸大得多的孔的边缘不清晰度来实现。使用 3 个不同的 X 射线管对两种方法的结果进行了比较。
{"title":"Measurement of Focal Spots of X-ray Tubes Using a CT Reconstruction Approach on Edge Images of Large Holes and Comparison to Pinhole Imaging","authors":"U. Zscherpel, Seyedreza Hashemi","doi":"10.58286/29556","DOIUrl":"https://doi.org/10.58286/29556","url":null,"abstract":"\u0000The first Non-destructive testing (NDT) method which evolved in the industrial age was radiographic testing (RT) [1]. Among all NDT methods, RT is no exception, so there are still many issues for optimizations even today. One of them is the measurement of the focal spot of X-ray tubes [2]. The size of the focal spot is critical for imaging, because it determines the spatial resolution in the X-ray image. The classical way to evaluate focal spots of X-ray tubes is by pinhole imaging using a camera obscura [1]. But this method has a natural lower limit, which is defined by the diameter of the pinhole used (today min. 10 µm) [2]. Therefore, focal spot sizes lower than 50 µm diameter cannot be imaged and measured correctly. An alternative approach, which permits this, was investigated here using the edge unsharpness of holes much larger than the focal spot size. The results of both methods were compared using 3 different X-ray tubes.\u0000","PeriodicalId":495540,"journal":{"name":"Research and Review Journal of Nondestructive Testing","volume":"26 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141232007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The subject of the article is the use of the Digital Image Correlation (DIC) technique in tests of damage detection in a composite cantilevered beam. Laboratory tests of the beam were conducted using the Q-400 system from Dantec Dynamics GmbH. The research aimed to study the behaviour of the structure under external forces and to analyse the influence of cross-section damage on the displacement field of the beam. The analysed quantities were also the changes in strain fields of the structure. For the laboratory model, the finite element models were prepared, and satisfactory compliance in terms of displacement fields between numerical and laboratory models for undamaged structure was obtained. The research has shown, that it is possible to indicate the approximate location of damage based on the information about changes in the displacement field.
{"title":"Using the DIC Technique in Damage Detection for a Cantilevered Composite Beam","authors":"Anna Rzepka, D. Ziaja","doi":"10.58286/29389","DOIUrl":"https://doi.org/10.58286/29389","url":null,"abstract":"\u0000The subject of the article is the use of the Digital Image Correlation (DIC) technique in tests of damage\u0000\u0000detection in a composite cantilevered beam. Laboratory tests of the beam were conducted using the Q-400 system\u0000\u0000from Dantec Dynamics GmbH. The research aimed to study the behaviour of the structure under external forces\u0000\u0000and to analyse the influence of cross-section damage on the displacement field of the beam. The analysed quantities\u0000\u0000were also the changes in strain fields of the structure. For the laboratory model, the finite element models were\u0000\u0000prepared, and satisfactory compliance in terms of displacement fields between numerical and laboratory models\u0000\u0000for undamaged structure was obtained. The research has shown, that it is possible to indicate the approximate\u0000\u0000location of damage based on the information about changes in the displacement field.\u0000","PeriodicalId":495540,"journal":{"name":"Research and Review Journal of Nondestructive Testing","volume":"1 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140272584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents a new methodology for noncontact measurement of the axial force of bolts in their tightening processes using laser-generated ultrasound waves. This method employs ultrasound waves scattered in a bolt shaft to detect axial force changes, while most conventional ultrasonic methods use ultrasound waves propagating linearly along the bolt axis. The ultrasound waves in this study are generated by laser irradiation on the top surface of a bolt. Subsequently, they propagate deeply into the shaft and return towards the top of the bolt through complicated paths due to the multiple scattering in the bolt shaft. Finally, they are detected at the top surface using another laser and a speckle knife edge detector. With an examination based on the finite element analysis and verification experiments, it has been shown that the waveform of the scattered ultrasound shifts in time linearly with increasing the axial force. The time shifts were estimated using the cross-correlation analysis between the measured waveforms and the reference waveform with no axial force. This result demonstrates the feasibility of estimating the change in axial force during tightening processes once the relationship between the time shifts and axial force is obtained for the specific type of bolt to be used in products. Furthermore, the proposed technique does not require machining to flatten a bolt's head and the end, while conventional ultrasonic methods need the flattening procedures, enabling fast, cost-effective axial force measurement in mass production manufacturing processes.
{"title":"Noncontact measurement of bolt axial force during tightening processes using scattered laser ultrasonic waves","authors":"So Kitazawa, Yong Lee, Rikesh Patel","doi":"10.58286/28211","DOIUrl":"https://doi.org/10.58286/28211","url":null,"abstract":"This paper presents a new methodology for noncontact measurement of the axial force of bolts in their tightening processes using laser-generated ultrasound waves. This method employs ultrasound waves scattered in a bolt shaft to detect axial force changes, while most conventional ultrasonic methods use ultrasound waves propagating linearly along the bolt axis. The ultrasound waves in this study are generated by laser irradiation on the top surface of a bolt. Subsequently, they propagate deeply into the shaft and return towards the top of the bolt through complicated paths due to the multiple scattering in the bolt shaft. Finally, they are detected at the top surface using another laser and a speckle knife edge detector. With an examination based on the finite element analysis and verification experiments, it has been shown that the waveform of the scattered ultrasound shifts in time linearly with increasing the axial force. The time shifts were estimated using the cross-correlation analysis between the measured waveforms and the reference waveform with no axial force. This result demonstrates the feasibility of estimating the change in axial force during tightening processes once the relationship between the time shifts and axial force is obtained for the specific type of bolt to be used in products. Furthermore, the proposed technique does not require machining to flatten a bolt's head and the end, while conventional ultrasonic methods need the flattening procedures, enabling fast, cost-effective axial force measurement in mass production manufacturing processes.","PeriodicalId":495540,"journal":{"name":"Research and Review Journal of Nondestructive Testing","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135872903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}