Methods for Incorporating the Effects of LWR Coolant Environments in Pressure Vessel and Piping Fatigue Evaluations

Methods for Incorporating the Effects of LWR Coolant Environments in Pressure Vessel and Piping Fatigue Evaluations PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 18

Get Book Here

Book Description
This paper summarizes the work performed at Argonne National Laboratory on the fatigue of piping and pressure vessel steels in the coolant environments of light water reactors. The existing fatigue strain vs. life ({var_epsilon}-N) data were evaluated to establish the effects of various material and loading variables, such as steel type, strain range, strain rate, temperature, and dissolved-oxygen level in water, on the fatigue lives of these steels. Statistical models are presented for estimating the fatigue {var_epsilon}-N curves for carbon and low-alloy steels and austenitic stainless steels as a function of material, loading, and environment variables. Case studies of fatigue failures in nuclear power plants are presented, and the contribution of environmental effects to crack initiation is discussed. Methods for incorporating environmental effects into the ASME Code fatigue evaluations are discussed. Data available in the literature have been reviewed to evaluate the possible conservatism in the existing fatigue design curves of the ASME Code.

Methods for Incorporating the Effects of LWR Coolant Environments in Pressure Vessel and Piping Fatigue Evaluations

Methods for Incorporating the Effects of LWR Coolant Environments in Pressure Vessel and Piping Fatigue Evaluations PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 18

Get Book Here

Book Description
This paper summarizes the work performed at Argonne National Laboratory on the fatigue of piping and pressure vessel steels in the coolant environments of light water reactors. The existing fatigue strain vs. life ({var_epsilon}-N) data were evaluated to establish the effects of various material and loading variables, such as steel type, strain range, strain rate, temperature, and dissolved-oxygen level in water, on the fatigue lives of these steels. Statistical models are presented for estimating the fatigue {var_epsilon}-N curves for carbon and low-alloy steels and austenitic stainless steels as a function of material, loading, and environment variables. Case studies of fatigue failures in nuclear power plants are presented, and the contribution of environmental effects to crack initiation is discussed. Methods for incorporating environmental effects into the ASME Code fatigue evaluations are discussed. Data available in the literature have been reviewed to evaluate the possible conservatism in the existing fatigue design curves of the ASME Code.

Methods for Incorporating Effects of LWR Coolant Environment Into ASME Code Fatigue Evaluations

Methods for Incorporating Effects of LWR Coolant Environment Into ASME Code Fatigue Evaluations PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 14

Get Book Here

Book Description
The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Appendix I to Section HI of the Code specifies design fatigue curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Recent test data illustrate potentially significant effects of LWR environments on the fatigue resistance of carbon and low-alloy steels and austenitic stainless steels (SSs). Under certain loading and environmental conditions, fatigue lives of carbon and low-alloy steels can be a factor of (almost equal to)70 lower in an LWR environment than in air. These results raise the issue of whether the design fatigue curves in Section III are appropriate for the intended purpose. This paper presents the two methods that have been proposed for incorporating the effects of LWR coolant environments into the ASME Code fatigue evaluations. The mechanisms of fatigue crack initiation in carbon and low-alloy steels and austenitic SSs in LWR environments are discussed.

Methods for Incorporating the Effects of LWR Coolant Environments in Pressure Vessel and Piping Fatique Evaluation

Methods for Incorporating the Effects of LWR Coolant Environments in Pressure Vessel and Piping Fatique Evaluation PDF Author: O. K. Chopra
Publisher:
ISBN:
Category : Austenitic stainless steel
Languages : en
Pages : 18

Get Book Here

Book Description


Effect of Material Heat Treatment on Fatigue Crack Initiation in Austenitic Stainless Steels in LWR Environments

Effect of Material Heat Treatment on Fatigue Crack Initiation in Austenitic Stainless Steels in LWR Environments PDF Author:
Publisher:
ISBN:
Category : Austenitic stainless steel
Languages : en
Pages : 44

Get Book Here

Book Description


Proceedings of the ASME Pressure Vessels and Piping Conference--2005: Codes and standards

Proceedings of the ASME Pressure Vessels and Piping Conference--2005: Codes and standards PDF Author:
Publisher: American Society of Mechanical Engineers
ISBN:
Category : Science
Languages : en
Pages : 410

Get Book Here

Book Description


Proceedings of the ASME Pressure Vessels and Piping Conference--2006: Codes and standards

Proceedings of the ASME Pressure Vessels and Piping Conference--2006: Codes and standards PDF Author:
Publisher:
ISBN:
Category : Aeroelasticity
Languages : en
Pages : 612

Get Book Here

Book Description


Mechanism and Estimation of Fatigue Crack Initiation in Austenitic Stainless Steels in LWR Environments

Mechanism and Estimation of Fatigue Crack Initiation in Austenitic Stainless Steels in LWR Environments PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Figures I-9.1 through I-9.6 of Appendix I to Section III of the Code specify fatigue design curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Existing fatigue strain-vs.-life ({var_epsilon}-N) data illustrate potentially significant effects of LWR coolant environments on the fatigue resistance of pressure vessel and piping steels. This report provides an overview of fatigue crack initiation in austenitic stainless steels in LWR coolant environments. The existing fatigue {var_epsilon}-N data have been evaluated to establish the effects of key material, loading, and environmental parameters (such as steel type, strain range, strain rate, temperature, dissolved-oxygen level in water, and flow rate) on the fatigue lives of these steels. Statistical models are presented for estimating the fatigue {var_epsilon}-N curves for austenitic stainless steels as a function of the material, loading, and environmental parameters. Two methods for incorporating environmental effects into the ASME Code fatigue evaluations are presented. The influence of reactor environments on the mechanism of fatigue crack initiation in these steels is also discussed.

Proceedings of the 15th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors

Proceedings of the 15th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors PDF Author: Gabriell Ilevbare
Publisher: Springer
ISBN: 3319487604
Category : Technology & Engineering
Languages : en
Pages : 2354

Get Book Here

Book Description
This 15th Edition of the International Conference on Materials Degradation in Light Water Reactors focuses on subject areas critical to the safe and efficient running of nuclear reactor systems through the exchange and discussion of reseach results as well as field operating and management experience.

Design and Analysis of Pressure Vessels and Piping

Design and Analysis of Pressure Vessels and Piping PDF Author: Dennis K. Williams
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 198

Get Book Here

Book Description


Fatigue Assessment in Light Water Reactors for Long Term Operation

Fatigue Assessment in Light Water Reactors for Long Term Operation PDF Author: IAEA
Publisher: International Atomic Energy Agency
ISBN: 9201284225
Category : Technology & Engineering
Languages : en
Pages : 168

Get Book Here

Book Description
Fatigue is a major element in time limited ageing analysis for long term operation of nuclear power plants (NPPs). It is important to understand how cracks occur and grow as a result of fatigue, and then assess fatigue failure. In the design and operating phase of NPPs, it is essential to consider the concurrent loadings associated with the design transients, thermal stratification, seismically induced stress cycles, and all relevant loads due to the various operational modes. After repeated cyclic loading, crack initiation can occur at the most highly affected locations if sufficient localized micro-structural damage has accumulated. This publication provides practical guidelines on how to identify and manage fatigue issues in NPPs. It explains the mechanism of fatigue, identifies which elements are the major contributors, and details how fatigue can be minimized in the design phase for new NPPs.