T. Zou, Zhiheng Zhang, Weiqin Tang, Dayong Li, Ying-hong Peng
The properties inhomogeneity of steel plates will result in uncertainty of forming quality of large diameter UOE oil pipes and increase the risk of pipeline failure. In this paper, a robust design method for UOE forming process based on support vector machine and sequential response surface modeling and considering the variation of steel plates' properties is proposed. A hundred of mechanical experiments are firstly carried out and the variation of X80 steel's properties is statistically evaluated. The varied properties are assigned to partitioned steel segments and taken as the noise factor in process design. The ovality of the UOE pipe is employed as the optimization objective, and the forming quality indicators including convex amount, mean outside diameter, yield strengths and Ys/Uts, O-forming gap, the width of the U-shaped plate, inclined angle of straight arm of the U-shaped plate, etc., are taken as the constraints. Based on the semi-analytical computation of C-, U- and O-forming processes and finite element simulation of expanding process, a sequential response surface model is established by using the support vector machine method. Finally, a Monte Carlo sampling is performed to demonstrate the effectiveness of the proposed method. Compared to conventional optimization method, the robust optimization performs obviously better in reducing the ovality and increasing the robustness of UOE forming process.
{"title":"Robust Optimization Of UOE Forming Process Considering Inhomogeneity Of Material Properties","authors":"T. Zou, Zhiheng Zhang, Weiqin Tang, Dayong Li, Ying-hong Peng","doi":"10.1115/1.4062588","DOIUrl":"https://doi.org/10.1115/1.4062588","url":null,"abstract":"\u0000 The properties inhomogeneity of steel plates will result in uncertainty of forming quality of large diameter UOE oil pipes and increase the risk of pipeline failure. In this paper, a robust design method for UOE forming process based on support vector machine and sequential response surface modeling and considering the variation of steel plates' properties is proposed. A hundred of mechanical experiments are firstly carried out and the variation of X80 steel's properties is statistically evaluated. The varied properties are assigned to partitioned steel segments and taken as the noise factor in process design. The ovality of the UOE pipe is employed as the optimization objective, and the forming quality indicators including convex amount, mean outside diameter, yield strengths and Ys/Uts, O-forming gap, the width of the U-shaped plate, inclined angle of straight arm of the U-shaped plate, etc., are taken as the constraints. Based on the semi-analytical computation of C-, U- and O-forming processes and finite element simulation of expanding process, a sequential response surface model is established by using the support vector machine method. Finally, a Monte Carlo sampling is performed to demonstrate the effectiveness of the proposed method. Compared to conventional optimization method, the robust optimization performs obviously better in reducing the ovality and increasing the robustness of UOE forming process.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44533015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Norihiko Hana, M. Umeda, Masao Akiyoshi, Kazushi Mitamura, K. Amaya
A new crack identification method that estimates the cracks in invisible locations based on the surface deformation measured by digital image correlation (DIC) is developed. An inverse problem is set up to estimate such invisible cracks from surface deformations. The inverse problem has an ill-condition because of noise contained in surface deformations. Our proposed regularization method uses prior information and Expectation a Posteriori (EAP) estimation. Prior information includes candidate crack shapes and surface deformations due to cracks. The candidate crack shapes are created by determining a crack's starting point and propagating it based on the force at its perimeter (ligament). A prior distribution is the surface deformations due to the candidate crack shapes. The likelihood distribution is a surface deformation measured by the DIC method. A posterior distribution is defined from the prior and likelihood distributions. In this study, the estimated result is the expected value of the posterior distribution. The validation test was performed, and the result shows that the proposed method superior to conventional L1-norm regularization method.
{"title":"Crack Identification by Digital Image Correlation Method Using Crack Shape as Prior Information","authors":"Norihiko Hana, M. Umeda, Masao Akiyoshi, Kazushi Mitamura, K. Amaya","doi":"10.1115/1.4062551","DOIUrl":"https://doi.org/10.1115/1.4062551","url":null,"abstract":"\u0000 A new crack identification method that estimates the cracks in invisible locations based on the surface deformation measured by digital image correlation (DIC) is developed. An inverse problem is set up to estimate such invisible cracks from surface deformations. The inverse problem has an ill-condition because of noise contained in surface deformations. Our proposed regularization method uses prior information and Expectation a Posteriori (EAP) estimation. Prior information includes candidate crack shapes and surface deformations due to cracks. The candidate crack shapes are created by determining a crack's starting point and propagating it based on the force at its perimeter (ligament). A prior distribution is the surface deformations due to the candidate crack shapes. The likelihood distribution is a surface deformation measured by the DIC method. A posterior distribution is defined from the prior and likelihood distributions. In this study, the estimated result is the expected value of the posterior distribution. The validation test was performed, and the result shows that the proposed method superior to conventional L1-norm regularization method.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46460577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Various fields in engineering explore the applicability of deep learning within condition monitoring. With the resurgence of nuclear energy due to electricity and carbon-free power generation demand, ensuring safe operations at nuclear power plants is important. Nuclear safety systems can undergo vibrations due to operating loads such as pump operations, flow-induced, etc. Safety equipment-piping systems experience degradation over the course of time due to flow-accelerated erosion and corrosion. Undetected degradation at certain locations can be subjected to a buildup of cyclic fatigue due to operational vibrations and thermal cycles. A condition monitoring framework is required to avoid fatigue cracking and for early detection of degraded locations along with severity of degradation. This study aims to propose a condition monitoring methodology for nuclear equipment-piping subject to pump-induced vibrations during normal operations by designing a novel feature extraction technique, exploring parameters and developing a deep neural network, incorporating uncertainty in degradation severity, conducting a thorough investigation of predicted results to analyze erroneous predictions, and proposing strategic recommendations for “safe” pump operating speeds, as per ASME design criteria. Even with nondestructive testing, detection of fatigue in pipes continues to be a difficult problem. Thus, this novel strategic recommendation to the operator can be beneficial in avoiding fatigue in piping systems due to pump-induced vibrations. The effectiveness of the proposed framework is demonstrated on a Z-piping system connected to an auxiliary pump from Experimental Breeder Reactor II nuclear reactor and a high prediction accuracy is achieved.
{"title":"Condition Monitoring of Nuclear Equipment-piping Systems Subjected to Normal Operating Loads Using Deep Neural Networks","authors":"H. Sandhu, S. Bodda, Serena Sauers, Abhinav Gupta","doi":"10.1115/1.4062462","DOIUrl":"https://doi.org/10.1115/1.4062462","url":null,"abstract":"\u0000 Various fields in engineering explore the applicability of deep learning within condition monitoring. With the resurgence of nuclear energy due to electricity and carbon-free power generation demand, ensuring safe operations at nuclear power plants is important. Nuclear safety systems can undergo vibrations due to operating loads such as pump operations, flow-induced, etc. Safety equipment-piping systems experience degradation over the course of time due to flow-accelerated erosion and corrosion. Undetected degradation at certain locations can be subjected to a buildup of cyclic fatigue due to operational vibrations and thermal cycles. A condition monitoring framework is required to avoid fatigue cracking and for early detection of degraded locations along with severity of degradation. This study aims to propose a condition monitoring methodology for nuclear equipment-piping subject to pump-induced vibrations during normal operations by designing a novel feature extraction technique, exploring parameters and developing a deep neural network, incorporating uncertainty in degradation severity, conducting a thorough investigation of predicted results to analyze erroneous predictions, and proposing strategic recommendations for “safe” pump operating speeds, as per ASME design criteria. Even with nondestructive testing, detection of fatigue in pipes continues to be a difficult problem. Thus, this novel strategic recommendation to the operator can be beneficial in avoiding fatigue in piping systems due to pump-induced vibrations. The effectiveness of the proposed framework is demonstrated on a Z-piping system connected to an auxiliary pump from Experimental Breeder Reactor II nuclear reactor and a high prediction accuracy is achieved.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48275147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Q. Feng, Qun Chang, H. Jia, Yi Wu, L. Dai, Yuguang Cao
The failure accidents in girth weld of pipelines occur frequently due to the combination of internal defects and external loads., However, the research on the fracture behavior of girth weld defects is relatively poor at present. To solve this problem, the cracking behavior and strain evolution law of the inner wall defects of the pipe girth weld is studied in combination with full-scale tests (FST). The constitutive and GTN damage parameters of the pipe base metal zone, weld zone and heat-affected zone (HAZ) are calibrated through the small punch test (SPT) and single edge notch bending (SENB) test. On this basis, the welded pipe model with inner wall defects is established, and a numerical simulation method for dynamic fracture behavior based on damage mechanics is formed. The numerical simulation method is verified by FST data and theoretical calculation. The results show that the numerical results are consistent with the FST and theoretical calculation in the elastic stage, plastic stage and fracture stage, and the error is within 10%. The novel numerical simulation method is provided as a means for the fracture behavior research of pipeline girth weld.
{"title":"Study on Numerical Simulation Method of Fracture Behavior of Pipeline Girth Weld","authors":"Q. Feng, Qun Chang, H. Jia, Yi Wu, L. Dai, Yuguang Cao","doi":"10.1115/1.4062461","DOIUrl":"https://doi.org/10.1115/1.4062461","url":null,"abstract":"\u0000 The failure accidents in girth weld of pipelines occur frequently due to the combination of internal defects and external loads., However, the research on the fracture behavior of girth weld defects is relatively poor at present. To solve this problem, the cracking behavior and strain evolution law of the inner wall defects of the pipe girth weld is studied in combination with full-scale tests (FST). The constitutive and GTN damage parameters of the pipe base metal zone, weld zone and heat-affected zone (HAZ) are calibrated through the small punch test (SPT) and single edge notch bending (SENB) test. On this basis, the welded pipe model with inner wall defects is established, and a numerical simulation method for dynamic fracture behavior based on damage mechanics is formed. The numerical simulation method is verified by FST data and theoretical calculation. The results show that the numerical results are consistent with the FST and theoretical calculation in the elastic stage, plastic stage and fracture stage, and the error is within 10%. The novel numerical simulation method is provided as a means for the fracture behavior research of pipeline girth weld.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41738157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper begins with derivation of true stress - true strain data, including post-necking section. Available results of past uni-axial tests on round 10 mm diameter and 200 mm long mild steel samples are the basis of the conversion. The steel in question was used to manufacture ten torispherical domes which were in the past tested for burst. Hence the relevance of matching material model necessary for the FE analyses. In the past plastic instability and constraints on the magnitude of plastic strains were postulated as criteria for the burst of internally pressurised torispheres. These criteria for burstpressure are being examined and benchmarked against the tests. The current paper, using the FE analyses, shows that modification of constraints on plastic strains has only marginal effect on the burst which still remains on the unsafe side of test data by a sizeable margin. The same is found to be true for plastic instability criterion. Subsequent computations moved back to the use of engineering stress-strain. Then two types of computing are carried out here, based on: multi-segment and bilinear modelling of material. Computed results of burst pressure follow the test data to within (-6%, +10%). These results are far better than all the previous.
{"title":"Burst of internally Pressurised Steel Torispheres","authors":"J. Błachut","doi":"10.1115/1.4062432","DOIUrl":"https://doi.org/10.1115/1.4062432","url":null,"abstract":"\u0000 The paper begins with derivation of true stress - true strain data, including post-necking section. Available results of past uni-axial tests on round 10 mm diameter and 200 mm long mild steel samples are the basis of the conversion. The steel in question was used to manufacture ten torispherical domes which were in the past tested for burst. Hence the relevance of matching material model necessary for the FE analyses.\u0000 In the past plastic instability and constraints on the magnitude of plastic strains were postulated as criteria for the burst of internally pressurised torispheres. These criteria for burstpressure are being examined and benchmarked against the tests.\u0000 The current paper, using the FE analyses, shows that modification of constraints on plastic strains has only marginal effect on the burst which still remains on the unsafe side of test data by a sizeable margin. The same is found to be true for plastic instability criterion.\u0000 Subsequent computations moved back to the use of engineering stress-strain. Then two types of computing are carried out here, based on: multi-segment and bilinear modelling of material. Computed results of burst pressure follow the test data to within (-6%, +10%). These results are far better than all the previous.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43278859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fatna Telli, M. Mokhtari, Elamine Abdelouahed, H. Benzaama, Kaoutar Khedim
Elbows in pressurized tubular structures are increasingly stressed by loadings with radial and tangential stresses. These stresses are completely different from those of straight tubular structures. Through the finite element method and using the ABAQUS computer code, the damage of a tubular structure in X60 of an elbow attached by straight parts stressed in internal pressure and in the moment of bending in closing is analyzed in this work. As a proposal for reinforcement, this structure is previously heat-treated and partially at the level of the elbow. The formulation of the heat-treated X60 material is based on the concept of FGM materials (functional graded materials) where the graduation by volume fraction between the metal in its base and that previously heat-affected named HAZ is under a power function of a parameter named volume fraction index (n). The graded properties of HAZ in the base metal along the thickness of the tubular structure are introduced by row of finite elements using a proposed meshing technique. The elastic-plastic behavior of the HAZ-base metal mixture under the Voce model follows the equivalent stress flow theory of Von Mises. Through the use of the XFEM technique in the damage and the mesh proposed in the graduation, in the presence of the internal pressure, of the heat treatment by the graduation and these parameters, condition the response of the structure and the level of their damage.
{"title":"Using FGM Concept to Predict the Damage of Heat Treated Elbows Under Bending and Pressure Loading","authors":"Fatna Telli, M. Mokhtari, Elamine Abdelouahed, H. Benzaama, Kaoutar Khedim","doi":"10.1115/1.4062336","DOIUrl":"https://doi.org/10.1115/1.4062336","url":null,"abstract":"\u0000 Elbows in pressurized tubular structures are increasingly stressed by loadings with radial and tangential stresses. These stresses are completely different from those of straight tubular structures. Through the finite element method and using the ABAQUS computer code, the damage of a tubular structure in X60 of an elbow attached by straight parts stressed in internal pressure and in the moment of bending in closing is analyzed in this work. As a proposal for reinforcement, this structure is previously heat-treated and partially at the level of the elbow. The formulation of the heat-treated X60 material is based on the concept of FGM materials (functional graded materials) where the graduation by volume fraction between the metal in its base and that previously heat-affected named HAZ is under a power function of a parameter named volume fraction index (n). The graded properties of HAZ in the base metal along the thickness of the tubular structure are introduced by row of finite elements using a proposed meshing technique. The elastic-plastic behavior of the HAZ-base metal mixture under the Voce model follows the equivalent stress flow theory of Von Mises. Through the use of the XFEM technique in the damage and the mesh proposed in the graduation, in the presence of the internal pressure, of the heat treatment by the graduation and these parameters, condition the response of the structure and the level of their damage.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43667073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study is an industrial case study for the application of a validated flashing and hydraulic shock modeling approach to the safety and design of a reactor blow line. The maximum flow rate is important for sizing of downstream components. The high pressure of the blow and flashing of the liquid can result in significant forces on pipe bends and other geometrical features. Analysis and prediction of such forces are of importance for the structural design and anchoring of the piping. Another concern for a liquid blow under high pressure is the potential for condensation-induced hydraulic shock. The collapse of the flashed vapor to the liquid phase creating shock waves of large amplitudes is a serious safety concern. The CFD model used the homogeneous mixture model with a flashing model for phase change of the fluid. The properties of the fluid were defined by a custom function which interpolated between tabulated values of the thermodynamic and transport properties. The CFD simulations predicted the occurrence of a condensation hydraulic shock when the blow down is initiated with empty pipes and demonstrated that a hydraulic shock could be prevented with liquid-filled condition. The pipework geometry was also optimized to reduce the forces acting at the junctions. The vapor quality at the outlet as a result of flashing was estimated which is necessary for the design of downstream systems.
{"title":"Simulation of Liquor Blow, Thrust Force and Risk of Condensation Hydraulic Shock in a Pulp-digester Piping System","authors":"Andrew Carlson, C. Narayanan, D. Lakehal","doi":"10.1115/1.4062335","DOIUrl":"https://doi.org/10.1115/1.4062335","url":null,"abstract":"\u0000 This study is an industrial case study for the application of a validated flashing and hydraulic shock modeling approach to the safety and design of a reactor blow line. The maximum flow rate is important for sizing of downstream components. The high pressure of the blow and flashing of the liquid can result in significant forces on pipe bends and other geometrical features. Analysis and prediction of such forces are of importance for the structural design and anchoring of the piping. Another concern for a liquid blow under high pressure is the potential for condensation-induced hydraulic shock. The collapse of the flashed vapor to the liquid phase creating shock waves of large amplitudes is a serious safety concern. The CFD model used the homogeneous mixture model with a flashing model for phase change of the fluid. The properties of the fluid were defined by a custom function which interpolated between tabulated values of the thermodynamic and transport properties. The CFD simulations predicted the occurrence of a condensation hydraulic shock when the blow down is initiated with empty pipes and demonstrated that a hydraulic shock could be prevented with liquid-filled condition. The pipework geometry was also optimized to reduce the forces acting at the junctions. The vapor quality at the outlet as a result of flashing was estimated which is necessary for the design of downstream systems.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45230026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xian-Kui Zhu, B. Wiersma, William R. Johnson, R. Sindelar
Pressure vessels (PVs) are widely used in the energy industry. Accurate burst pressure is critical to structural design and safe operation for both thin and thick-walled PVs. The traditional strength theories utilized a single-parameter material property, such as the yield strength (YS) or the ultimate tensile strength (UTS) to develop failure models for determining the yield or ultimate pressure carrying capacity in the PV design. The UTS-based Barlow formula is a typical burst pressure model developed from the Tresca strength theory that provides the basis for developing regulation rules and failure models for different industry design codes, such as ASME BPVC, ASME B31.3, and ASME B31G, among others. In order to reduce the conservatism of the Tresca strength model, ASME BPVC recently adapted failure models developed from the von Mises strength theory for the PV design and analysis. It has been commonly accepted that the burst pressure of pipelines depends on the UTS and strain hardening exponent, n, of the pipeline steels. An average shear stress yield theory was thus developed, and the Zhu-Leis solution of burst pressure was obtained as a function of UTS and n for thin-walled line pipes. Experiments showed that the Zhu-Leis solution provides an accurate, reliable prediction of burst pressure for defect-free thin-walled pipes. In order to extend the Zhu-Leis solution to thick-walled cylindrical PVs, this paper defined three new flow stresses, modified the traditional strength theories, and obtained three new burst pressure solutions that are valid for both thin and thick-walled cylindrical vessels. The proposed flow stresses are able to describe the tensile strength and the plastic flow response of PVs for a strain hardening steel. The associated strength theories were then developed in terms of the Tresca, von Mises and Zhu-Leis yield criteria. From these new strength theories, three burst pressure solutions were obtained for thick-walled cylinders, where the von Mises solution is an upper bound prediction, the Tresca solution is a lower bound prediction, and the Zhu-Leis solution is an intermediate prediction of burst pressure for thick-walled cylinders. Finally, the proposed burst pressure solutions were evaluated and validated by two large datasets of full-scale burst tests for thick-walled tubes and for thin-walled pipes.
{"title":"Burst Pressure Solutions of Thin and Thick-Walled Cylindrical Vessels","authors":"Xian-Kui Zhu, B. Wiersma, William R. Johnson, R. Sindelar","doi":"10.1115/1.4062334","DOIUrl":"https://doi.org/10.1115/1.4062334","url":null,"abstract":"\u0000 Pressure vessels (PVs) are widely used in the energy industry. Accurate burst pressure is critical to structural design and safe operation for both thin and thick-walled PVs. The traditional strength theories utilized a single-parameter material property, such as the yield strength (YS) or the ultimate tensile strength (UTS) to develop failure models for determining the yield or ultimate pressure carrying capacity in the PV design. The UTS-based Barlow formula is a typical burst pressure model developed from the Tresca strength theory that provides the basis for developing regulation rules and failure models for different industry design codes, such as ASME BPVC, ASME B31.3, and ASME B31G, among others. In order to reduce the conservatism of the Tresca strength model, ASME BPVC recently adapted failure models developed from the von Mises strength theory for the PV design and analysis. It has been commonly accepted that the burst pressure of pipelines depends on the UTS and strain hardening exponent, n, of the pipeline steels. An average shear stress yield theory was thus developed, and the Zhu-Leis solution of burst pressure was obtained as a function of UTS and n for thin-walled line pipes. Experiments showed that the Zhu-Leis solution provides an accurate, reliable prediction of burst pressure for defect-free thin-walled pipes. In order to extend the Zhu-Leis solution to thick-walled cylindrical PVs, this paper defined three new flow stresses, modified the traditional strength theories, and obtained three new burst pressure solutions that are valid for both thin and thick-walled cylindrical vessels. The proposed flow stresses are able to describe the tensile strength and the plastic flow response of PVs for a strain hardening steel. The associated strength theories were then developed in terms of the Tresca, von Mises and Zhu-Leis yield criteria. From these new strength theories, three burst pressure solutions were obtained for thick-walled cylinders, where the von Mises solution is an upper bound prediction, the Tresca solution is a lower bound prediction, and the Zhu-Leis solution is an intermediate prediction of burst pressure for thick-walled cylinders. Finally, the proposed burst pressure solutions were evaluated and validated by two large datasets of full-scale burst tests for thick-walled tubes and for thin-walled pipes.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45284178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Zhang, Chaojie Hu, Jian-jun Yan, Yue Hu, Yang Gao, F. Xuan
Guided wave is a key nondestructive technique for structural health monitoring due to its high sensitivity to structural changes and long propagation distance. However, to achieve high accuracy for damage location, large quantity of samples and thousands of iterations are typically needed for detection algorithms. To address this, in this paper, an eXplainable Convolutional neural network for Multivariate time series classification (XCM) is adopted, which is composed of one-dimensional (1D) and two-dimensional (2D) convolution layers to achieve high accuracy damage location on pressure vessels with limited training sets. By further optimizing the network parameters and network structure, the training time is greatly reduced and the accuracy is further improved. The optimized XCM improves the damage location precision from 95.5% to 98% with small samples (training set/validation set/testing set=23/2/25) and low training epochs (under 100 epochs), suggesting that the XCM has great advantages in pressure vessel's damage location classification. its potential for guided wave-based damage detection technique in structural health monitoring.
导波对结构变化的灵敏度高，传播距离远，是结构健康监测的关键无损技术。然而，为了达到较高的损伤定位精度，检测算法通常需要大量的样本和数千次的迭代。针对这一问题，本文采用由一维(1D)和二维(2D)卷积层组成的可解释卷积神经网络(eXplainable Convolutional neural network for Multivariate time series classification, XCM)，在有限的训练集下实现压力容器的高精度损伤定位。通过进一步优化网络参数和网络结构，大大缩短了训练时间，进一步提高了准确率。优化后的XCM在小样本(训练集/验证集/测试集=23/2/25)和低训练次数(100次以下)下，将损伤定位精度从95.5%提高到98%，表明XCM在压力容器损伤定位分类中具有很大的优势。基于导波的损伤检测技术在结构健康监测中的应用潜力。
{"title":"Guided Wave Damage Location of Pressure Vessel Based On Optimized XCM Neural Network","authors":"J. Zhang, Chaojie Hu, Jian-jun Yan, Yue Hu, Yang Gao, F. Xuan","doi":"10.1115/1.4062276","DOIUrl":"https://doi.org/10.1115/1.4062276","url":null,"abstract":"\u0000 Guided wave is a key nondestructive technique for structural health monitoring due to its high sensitivity to structural changes and long propagation distance. However, to achieve high accuracy for damage location, large quantity of samples and thousands of iterations are typically needed for detection algorithms. To address this, in this paper, an eXplainable Convolutional neural network for Multivariate time series classification (XCM) is adopted, which is composed of one-dimensional (1D) and two-dimensional (2D) convolution layers to achieve high accuracy damage location on pressure vessels with limited training sets. By further optimizing the network parameters and network structure, the training time is greatly reduced and the accuracy is further improved. The optimized XCM improves the damage location precision from 95.5% to 98% with small samples (training set/validation set/testing set=23/2/25) and low training epochs (under 100 epochs), suggesting that the XCM has great advantages in pressure vessel's damage location classification. its potential for guided wave-based damage detection technique in structural health monitoring.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47626450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The increased usage of fiber reinforced plastic (FRP) composite pressure vessels and piping components in the past decades in the residential and industrial sectors is attributed to the FRP material resistance to corrosion and chemical attacks. FRP composite flanges are, however, known for their anisotropic behavior. In the ASME code section X, FRP composite flanges are treated using an analytical approach derived from that metallic flanges in addition to the fact that the geometries are made to fit them as much as possible and not designed independently. This is known to have caused structural flaws for certain FRP flange classes and sizes. Using a recently developed anisotropic FRP flange approach, it is proposed to identify the most critical flanges by analyzing the flange parameters such as flange ring rotation and stresses in their different parts; gasket, flange ring, hub, and shell subjected to pressure loading. The study on the strength of flanges described in ASME section X RD-620.1 table, will reveal the most critical size and class flanges and their highly stressed locations. To conduct such a study, the selected flange material is an E glass/Vinyl Ester laminate composite. The study shows that FRP flanges of classes 25 and 50 are most vulnerable and should comparatively be less loaded. The stresses are found to reach 50 MPa in the shell and 58 MPa in the flange ring while the maximum flange rotation is 0.83 deg.
在过去的几十年里，纤维增强塑料(FRP)复合压力容器和管道部件在住宅和工业部门的使用越来越多，这归功于FRP材料耐腐蚀和化学侵蚀。然而，FRP复合法兰因其各向异性而闻名。在美国机械工程师协会(ASME)规范第X节中，玻璃钢复合材料法兰的处理采用了从金属法兰中衍生出来的分析方法，此外，几何形状要尽可能地与金属法兰相适应，而不是单独设计。已知这导致了某些FRP法兰等级和尺寸的结构缺陷。采用近年来发展起来的各向异性玻璃钢法兰方法，通过分析法兰环旋转和各部位应力等参数，识别出最关键的法兰;垫圈、法兰环、轮毂和壳体承受压力载荷。对ASME X RD-620.1表中描述的法兰强度的研究将揭示最关键的尺寸和等级的法兰及其高应力位置。为了进行这样的研究，选择的法兰材料是E玻璃/乙烯基酯层压复合材料。研究表明，25级和50级的FRP法兰最脆弱，应相对减少载荷。当法兰最大旋转0.83°时，壳体内应力达到50 MPa，法兰环内应力达到58 MPa。
{"title":"Stress Analysis of ASME Section X Flanges Using Classical Lamination Theory","authors":"Sofiane Bouzid, Abdel-Hakim Bouzid, Anh-Dung Ngo","doi":"10.1115/1.4057029","DOIUrl":"https://doi.org/10.1115/1.4057029","url":null,"abstract":"Abstract The increased usage of fiber reinforced plastic (FRP) composite pressure vessels and piping components in the past decades in the residential and industrial sectors is attributed to the FRP material resistance to corrosion and chemical attacks. FRP composite flanges are, however, known for their anisotropic behavior. In the ASME code section X, FRP composite flanges are treated using an analytical approach derived from that metallic flanges in addition to the fact that the geometries are made to fit them as much as possible and not designed independently. This is known to have caused structural flaws for certain FRP flange classes and sizes. Using a recently developed anisotropic FRP flange approach, it is proposed to identify the most critical flanges by analyzing the flange parameters such as flange ring rotation and stresses in their different parts; gasket, flange ring, hub, and shell subjected to pressure loading. The study on the strength of flanges described in ASME section X RD-620.1 table, will reveal the most critical size and class flanges and their highly stressed locations. To conduct such a study, the selected flange material is an E glass/Vinyl Ester laminate composite. The study shows that FRP flanges of classes 25 and 50 are most vulnerable and should comparatively be less loaded. The stresses are found to reach 50 MPa in the shell and 58 MPa in the flange ring while the maximum flange rotation is 0.83 deg.","PeriodicalId":50080,"journal":{"name":"Journal of Pressure Vessel Technology-Transactions of the Asme","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136090935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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