Standards or codes for defects assessment usually accompany their own design standards, such as, ASME BPVC section VIII and API 579-1/ASME FFS-1, GB 150 and GB/T 19624. The development of defects assessment standards should be adapted to the design requirements of pressure vessels. The consistency between fitness-for-service (FFS) procedures and design requirements of pressure vessels is discussed in this work. As a key link between FFS procedures and design standards, the required material fracture toughness not only depends on the methods of FFS procedures such as failure assessment diagram, but also on the design requirements. A procedure based on failure assessment diagram under design requirements is proposed to calculate critical crack sizes. The result can give some meaningful suggestions for the development of standards or codes.
{"title":"Critical Crack Sizes of Pressure Vessels Based on Failure Assessment Diagram Under Design Requirements","authors":"Yuebing Li, Weiya Jin, Mingjue Zhou, Zengliang Gao","doi":"10.1115/pvp2019-93575","DOIUrl":"https://doi.org/10.1115/pvp2019-93575","url":null,"abstract":"\u0000 Standards or codes for defects assessment usually accompany their own design standards, such as, ASME BPVC section VIII and API 579-1/ASME FFS-1, GB 150 and GB/T 19624. The development of defects assessment standards should be adapted to the design requirements of pressure vessels. The consistency between fitness-for-service (FFS) procedures and design requirements of pressure vessels is discussed in this work. As a key link between FFS procedures and design standards, the required material fracture toughness not only depends on the methods of FFS procedures such as failure assessment diagram, but also on the design requirements. A procedure based on failure assessment diagram under design requirements is proposed to calculate critical crack sizes. The result can give some meaningful suggestions for the development of standards or codes.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128896811","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}
While there are many factors that should be considered when determining if a stud can be reused, one of them is the nut factor. The study described in this paper set out to determine if the nut factor of a Xylan 1424 coated stud is significantly affected by the age of the coating and/or the cycles of tightening. A load cell was used to compare the nut factor: 1) of previously installed (used) studs to new studs, 2) of a new and used stud that were tightened more than once, and 3) associated with the first tightening pass to subsequent passes for a new stud. The results show that the age of the stud and the amount it has been tightened contribute to an increased nut factor for used Xylan 1424 studs.
{"title":"A Study on the Reuse of Xylan 1424 Studs","authors":"M. Ruffin","doi":"10.1115/pvp2019-93628","DOIUrl":"https://doi.org/10.1115/pvp2019-93628","url":null,"abstract":"\u0000 While there are many factors that should be considered when determining if a stud can be reused, one of them is the nut factor. The study described in this paper set out to determine if the nut factor of a Xylan 1424 coated stud is significantly affected by the age of the coating and/or the cycles of tightening. A load cell was used to compare the nut factor: 1) of previously installed (used) studs to new studs, 2) of a new and used stud that were tightened more than once, and 3) associated with the first tightening pass to subsequent passes for a new stud. The results show that the age of the stud and the amount it has been tightened contribute to an increased nut factor for used Xylan 1424 studs.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127459340","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}
Piping made from thermoplastic fiber reinforced polymer composites (TP-FRPCs) is receiving increasing attention in the oil and gas industry. Creep and time-dependent behavior is one of the main factors defining the service life of TP-FRPC structures. The lifetime and time-dependent behavior of TP-FRPC structures can be predicted using simulation tools, such as finite element analysis, to aid in the design optimization by modeling the long-term behavior of the material. Composite material time-dependent properties are required inputs for such models. While there is previous research available on creep testing of TP-FRPCs in laminate geometry, such tests may not enable accurate determination of the composite properties due to edge effects. On the other hand, coupons with tubular geometry not only provide improved load distribution between the fibers and matrix with minimal end effects, they also enable certain loading conditions experienced during typical piping operations such as internal pressure. In this study, a testing method to capture the creep behavior of tubular TP-FRPC specimens subjected to multi-axial loading conditions was developed. Tubular coupons were prototyped by an automated tape placement process. Strain was measure using digital image correlation technique and strain gauges. The development of the test setup forms the foundation for further testing of tubular TP-FRPC coupons at different multi-axial loading conditions. As a preliminary test, the creep behavior of a TP-FRPC tube subjected to pure hoop stress condition was evaluated using the developed testing process.
{"title":"Development of Creep Test Method for Thermoplastic Fiber-Reinforced Polymer Composite Tubes Under Pure Hoop Loading Condition","authors":"H. Doan, H. Ashrafizadeh, P. Mertiny","doi":"10.1115/pvp2019-93302","DOIUrl":"https://doi.org/10.1115/pvp2019-93302","url":null,"abstract":"\u0000 Piping made from thermoplastic fiber reinforced polymer composites (TP-FRPCs) is receiving increasing attention in the oil and gas industry. Creep and time-dependent behavior is one of the main factors defining the service life of TP-FRPC structures. The lifetime and time-dependent behavior of TP-FRPC structures can be predicted using simulation tools, such as finite element analysis, to aid in the design optimization by modeling the long-term behavior of the material. Composite material time-dependent properties are required inputs for such models. While there is previous research available on creep testing of TP-FRPCs in laminate geometry, such tests may not enable accurate determination of the composite properties due to edge effects. On the other hand, coupons with tubular geometry not only provide improved load distribution between the fibers and matrix with minimal end effects, they also enable certain loading conditions experienced during typical piping operations such as internal pressure. In this study, a testing method to capture the creep behavior of tubular TP-FRPC specimens subjected to multi-axial loading conditions was developed. Tubular coupons were prototyped by an automated tape placement process. Strain was measure using digital image correlation technique and strain gauges. The development of the test setup forms the foundation for further testing of tubular TP-FRPC coupons at different multi-axial loading conditions. As a preliminary test, the creep behavior of a TP-FRPC tube subjected to pure hoop stress condition was evaluated using the developed testing process.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124350173","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}
One of the challenges of analyzing flow-induced vibration in piping systems is determining how to analytically characterize the loading related to the source of the vibration. Simplified methods can be sufficient for evaluating an existing piping configuration through correlation with vibration measurements. However, if vibration mitigation is required a more thoughtful analysis approach should be used so that the anticipated vibration responses of the post-modification piping configuration can be more accurately determined. Two case histories are presented that illustrate analysis approaches used to evaluate the severity of flow-induced piping vibration and also develop effective vibration mitigation designs. The analysis approaches used in both cases involved the simulation of vibration loading based on limited vibration data. Using the analysis approaches that were developed, vibration restraints were able to be effectively located and designed. The effectiveness of the analytically determined vibration mitigation solutions was confirmed by post-modification testing and observation.
{"title":"Analysis Approach Examples for Flow-Induced Piping Vibration Mitigation","authors":"B. Voll","doi":"10.1115/pvp2019-93314","DOIUrl":"https://doi.org/10.1115/pvp2019-93314","url":null,"abstract":"\u0000 One of the challenges of analyzing flow-induced vibration in piping systems is determining how to analytically characterize the loading related to the source of the vibration. Simplified methods can be sufficient for evaluating an existing piping configuration through correlation with vibration measurements. However, if vibration mitigation is required a more thoughtful analysis approach should be used so that the anticipated vibration responses of the post-modification piping configuration can be more accurately determined.\u0000 Two case histories are presented that illustrate analysis approaches used to evaluate the severity of flow-induced piping vibration and also develop effective vibration mitigation designs. The analysis approaches used in both cases involved the simulation of vibration loading based on limited vibration data. Using the analysis approaches that were developed, vibration restraints were able to be effectively located and designed. The effectiveness of the analytically determined vibration mitigation solutions was confirmed by post-modification testing and observation.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123928079","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}
Brittle fracture assessments (BFAs) of pressure vessels based on API 579-1/ASME FFS-1, Section 3 procedures are frequently easier and more straightforward to implement in comparison to the BFAs on piping systems. Specifically, the development of the MSOT curves. This is due to the complexities involved in the piping systems due to the branch piping interactions, end conditions of piping systems such as nozzle flexibilities at the pressure vessel connections, temperature changes in the length of piping especially when the piping is significantly long as seen in flare header piping systems. MSOT curves that are alternatively used for MAT curves provide a better picture to the plant personnel in understanding the safe operating envelope. Development of MSOT curves is an iterative process and therefore involves significant number of piping stress analyses during their development. In this paper, an approach to develop the MSOT curves is discussed with two case studies that are of relevance to olefin plants.
{"title":"Brittle Fracture Assessments on Piping Systems: MSOT Curves","authors":"I. Chakraborty, K. Subramanian, J. Penso","doi":"10.1115/pvp2019-93736","DOIUrl":"https://doi.org/10.1115/pvp2019-93736","url":null,"abstract":"\u0000 Brittle fracture assessments (BFAs) of pressure vessels based on API 579-1/ASME FFS-1, Section 3 procedures are frequently easier and more straightforward to implement in comparison to the BFAs on piping systems. Specifically, the development of the MSOT curves. This is due to the complexities involved in the piping systems due to the branch piping interactions, end conditions of piping systems such as nozzle flexibilities at the pressure vessel connections, temperature changes in the length of piping especially when the piping is significantly long as seen in flare header piping systems. MSOT curves that are alternatively used for MAT curves provide a better picture to the plant personnel in understanding the safe operating envelope. Development of MSOT curves is an iterative process and therefore involves significant number of piping stress analyses during their development. In this paper, an approach to develop the MSOT curves is discussed with two case studies that are of relevance to olefin plants.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122211424","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}
Design equation (4.3.1) for the minimum required thickness of a cylindrical shell subjected to internal pressure in Part 4 “design by rule (DBR)” of the ASME Boiler and Pressure Vessel Code, Section VIII, Division 2 [1] is based on the Tresca Yield Criterion, while design by analysis (DBA) in Part 5 of the Division 2 Code is based on the von Mises Yield Criterion. According to ASME PTB-1 “ASME Section VIII – Division 2 Criteria and Commentary”, the difference in results is about 15% due to use of the two different criteria. Although the von Mises Yield Criterion will result in a shell wall thickness less than that from Tresca Yield Criterion, Part 4 (DBR) of ASME Division 2 adopts the latter for a more convenient design equation. To use the von Mises Criterion in lieu of Tresca to reduce shell wall thickness, one has to follow DBA rules in Part 5 of Division 2, which typically requires detailed numeric analysis performed by experienced stress analysts. This paper proposes a simple design equation for the minimum required thickness of a cylindrical shell subjected to internal pressure based on the von Mises Yield Criterion. The equation is suitable for both thin and thick cylindrical shells. Calculation results from the equation are validated by results from limit load analyses in accordance with Part 5 of ASME Division 2 Code.
ASME锅炉和压力容器规范第8节第2部[1]第4部分“按规则设计(DBR)”中圆柱壳承受内压所需的最小厚度的设计方程(4.3.1)基于Tresca屈服准则，而第2部规范第5部分的分析设计(DBA)基于von Mises屈服准则。根据ASME PTB-1“ASME Section VIII - Division 2 Criteria and Commentary”，由于使用两种不同的标准，结果的差异约为15%。尽管von Mises屈服准则会导致壳体壁厚度小于Tresca屈服准则，但ASME第2部第4部分(DBR)采用了后者，以获得更方便的设计方程。要使用von Mises准则代替Tresca来减小壳体壁厚度，必须遵循第2部分第5部分中的DBA规则，这通常需要由经验丰富的应力分析人员执行详细的数值分析。本文提出了基于von Mises屈服准则的圆柱壳内压最小厚度的简单设计方程。该方程适用于薄圆柱壳和厚圆柱壳。根据美国机械工程师协会(ASME)第2部规范第5部分，用极限载荷分析的结果验证了公式的计算结果。
{"title":"Design Equation for Minimum Required Thickness of a Cylindrical Shell Subject to Internal Pressure Based on Von Mises Criterion","authors":"James Lu, B. Millet, K. Kirkpatrick, Bryan Mosher","doi":"10.1115/pvp2019-93155","DOIUrl":"https://doi.org/10.1115/pvp2019-93155","url":null,"abstract":"\u0000 Design equation (4.3.1) for the minimum required thickness of a cylindrical shell subjected to internal pressure in Part 4 “design by rule (DBR)” of the ASME Boiler and Pressure Vessel Code, Section VIII, Division 2 [1] is based on the Tresca Yield Criterion, while design by analysis (DBA) in Part 5 of the Division 2 Code is based on the von Mises Yield Criterion. According to ASME PTB-1 “ASME Section VIII – Division 2 Criteria and Commentary”, the difference in results is about 15% due to use of the two different criteria. Although the von Mises Yield Criterion will result in a shell wall thickness less than that from Tresca Yield Criterion, Part 4 (DBR) of ASME Division 2 adopts the latter for a more convenient design equation. To use the von Mises Criterion in lieu of Tresca to reduce shell wall thickness, one has to follow DBA rules in Part 5 of Division 2, which typically requires detailed numeric analysis performed by experienced stress analysts.\u0000 This paper proposes a simple design equation for the minimum required thickness of a cylindrical shell subjected to internal pressure based on the von Mises Yield Criterion. The equation is suitable for both thin and thick cylindrical shells. Calculation results from the equation are validated by results from limit load analyses in accordance with Part 5 of ASME Division 2 Code.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116197471","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}
Composite materials such as carbon-fiber-reinforced plastics (CFRP) and glass-fiber-reinforced plastics (GFRP) have been attracting much attention from the viewpoint of lightweight solution of automobiles and airplanes. However, the recyclability of these composite materials is not sufficient and the environmental load is large. Recently, self-reinforced polymer (SRP), in which similar polymer is used for reinforcing fibers and matrix, has been proposed. High-density polyethylene (HDPE) reinforced with ultra-high-molecular-weight polyethylene (UHMWPE) fibers, so-called self-reinforced PE (SRPE), is one of the promising thermoplastic composites. In this study, SRPE plates were made and the tensile tests were carried out. After the effect of reinforcement of UHMWPE fibers was evaluated on the basis of the tensile strength, the relationship between the distribution of UHMWPE fibers and the location of the final fracture line was examined. It was found from these experimental results that the fracture tends to occur along the regions with low area fraction of fibers or along those with low area fraction of fiber/matrix boundaries. This fact suggests that the fracture location of SRPs is predictable from the distribution of reinforcing fibers.
{"title":"Prediction of Fracture Location in Tensile Test of Short-Fiber-Self-Reinforced Polyethylene Composite Plates","authors":"N. Tada, M. Jin, T. Uemori, J. Sakamoto","doi":"10.1115/pvp2019-93546","DOIUrl":"https://doi.org/10.1115/pvp2019-93546","url":null,"abstract":"\u0000 Composite materials such as carbon-fiber-reinforced plastics (CFRP) and glass-fiber-reinforced plastics (GFRP) have been attracting much attention from the viewpoint of lightweight solution of automobiles and airplanes. However, the recyclability of these composite materials is not sufficient and the environmental load is large. Recently, self-reinforced polymer (SRP), in which similar polymer is used for reinforcing fibers and matrix, has been proposed. High-density polyethylene (HDPE) reinforced with ultra-high-molecular-weight polyethylene (UHMWPE) fibers, so-called self-reinforced PE (SRPE), is one of the promising thermoplastic composites. In this study, SRPE plates were made and the tensile tests were carried out. After the effect of reinforcement of UHMWPE fibers was evaluated on the basis of the tensile strength, the relationship between the distribution of UHMWPE fibers and the location of the final fracture line was examined. It was found from these experimental results that the fracture tends to occur along the regions with low area fraction of fibers or along those with low area fraction of fiber/matrix boundaries. This fact suggests that the fracture location of SRPs is predictable from the distribution of reinforcing fibers.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124947218","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}
Printed circuit heat exchangers (PCHEs) are used in a number of novel nuclear reactor designs. In order to use a PCHE as a primary coolant confinement unit in the United States, the stress and strain must be modeled under realistic service loads, and shown to remain within limits imposed by ASME standards. Due to the complex geometry and multi-length scale features, direct simulation of the stress and strain in a utility scale PCHE is not practical because of the large number of degrees of freedom. This work presents an algorithm to model damage to the core region of a PCHE using planar 2D formulation and realistic service loads. We compare how closely the results from three different planar formulations match the results of a corresponding 3D model. We also explore other ways of reducing the size of the numerical model required to accurately simulate the stress and strain in the core region of a PCHE. Finally, we perform strain-limits evaluation on a core region of a PCHE using fully temperature coupled, elastic perfectly plastic material properties, and realistic service loads, obtained from plant dynamics code of sodium cooled fast reactor coupled with a supercritical CO2 Brayton cycle. For our analyses, we used CSIMSOFT Trelis: a commercial meshing software, Multi Object Oriented Solver Environment (MOOSE): an open source finite elements solver, and Paraview: an open source post processing tool. Our methodology is presented and discussed in sufficient detail so that the work can be reproduced by others.
{"title":"Advances Towards Elastic-Perfectly Plastic Simulation of the Core of Printed Circuit Heat Exchangers","authors":"Alon Katz, Devesh Ranjan","doi":"10.1115/pvp2019-93807","DOIUrl":"https://doi.org/10.1115/pvp2019-93807","url":null,"abstract":"\u0000 Printed circuit heat exchangers (PCHEs) are used in a number of novel nuclear reactor designs. In order to use a PCHE as a primary coolant confinement unit in the United States, the stress and strain must be modeled under realistic service loads, and shown to remain within limits imposed by ASME standards. Due to the complex geometry and multi-length scale features, direct simulation of the stress and strain in a utility scale PCHE is not practical because of the large number of degrees of freedom. This work presents an algorithm to model damage to the core region of a PCHE using planar 2D formulation and realistic service loads. We compare how closely the results from three different planar formulations match the results of a corresponding 3D model. We also explore other ways of reducing the size of the numerical model required to accurately simulate the stress and strain in the core region of a PCHE. Finally, we perform strain-limits evaluation on a core region of a PCHE using fully temperature coupled, elastic perfectly plastic material properties, and realistic service loads, obtained from plant dynamics code of sodium cooled fast reactor coupled with a supercritical CO2 Brayton cycle. For our analyses, we used CSIMSOFT Trelis: a commercial meshing software, Multi Object Oriented Solver Environment (MOOSE): an open source finite elements solver, and Paraview: an open source post processing tool. Our methodology is presented and discussed in sufficient detail so that the work can be reproduced by others.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133092532","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}
Min Xu, Yujie Zhao, Bin Zhou, Xiao-hua He, Chang-yu Zhou
Based on the Hill yield criterion, the analytical solutions of the limit load of orthotropic thick-walled pipes under pure internal pressure, bending moment and torsion are given respectively. The simplified Mises analytical solution and finite element results of limit load for isotropic thick-walled pipe are obtained. The solution verifies the reliability of the analytical solution. The paper discusses the difference of limit load of isotropic and orthotropic pipes under the conditions of pure internal pressure, pure bending moment and pure torsion moment. It is concluded that the influence of material anisotropy on the limit load is significant. The limit load of pipe under pure internal pressure is mainly determined by circumferential yield strength, pure bending is only related to axial yield strength and pure torsion moment is related to the yield strength in the 45° direction and radial yield strength.
{"title":"Limit Load Solutions of the Orthotropic Thick-Walled Pipe Subjected to Internal Pressure, Bending Moment and Torsion Moment","authors":"Min Xu, Yujie Zhao, Bin Zhou, Xiao-hua He, Chang-yu Zhou","doi":"10.1115/pvp2019-93377","DOIUrl":"https://doi.org/10.1115/pvp2019-93377","url":null,"abstract":"\u0000 Based on the Hill yield criterion, the analytical solutions of the limit load of orthotropic thick-walled pipes under pure internal pressure, bending moment and torsion are given respectively. The simplified Mises analytical solution and finite element results of limit load for isotropic thick-walled pipe are obtained. The solution verifies the reliability of the analytical solution. The paper discusses the difference of limit load of isotropic and orthotropic pipes under the conditions of pure internal pressure, pure bending moment and pure torsion moment. It is concluded that the influence of material anisotropy on the limit load is significant. The limit load of pipe under pure internal pressure is mainly determined by circumferential yield strength, pure bending is only related to axial yield strength and pure torsion moment is related to the yield strength in the 45° direction and radial yield strength.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130388013","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}
During inspection of a heating coil in the convection section of a steam reformer, significant thickness loss due to external corrosion was discovered in a large number of tubes. In order to optimize the scope of repairs and ensure further safe operation, a level 3 fitness-for-service and remaining life analysis were performed in accordance with API-579. This paper will describe the fitness-for-service assessment that was performed, first using an idealized geometry, and thereafter using the actual corroded geometry of a removed tube. The procedure used to estimate the remaining life of the damaged coil will also be presented.
{"title":"Fitness-for-Service Assessment of Externally Corroded Convection Coil Tube","authors":"G. Zyl, Abdullatif Al-Salmi","doi":"10.1115/pvp2019-93829","DOIUrl":"https://doi.org/10.1115/pvp2019-93829","url":null,"abstract":"\u0000 During inspection of a heating coil in the convection section of a steam reformer, significant thickness loss due to external corrosion was discovered in a large number of tubes.\u0000 In order to optimize the scope of repairs and ensure further safe operation, a level 3 fitness-for-service and remaining life analysis were performed in accordance with API-579.\u0000 This paper will describe the fitness-for-service assessment that was performed, first using an idealized geometry, and thereafter using the actual corroded geometry of a removed tube. The procedure used to estimate the remaining life of the damaged coil will also be presented.","PeriodicalId":150804,"journal":{"name":"Volume 3: Design and Analysis","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114724036","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：