ML18267A095
| ML18267A095 | |
| Person / Time | |
|---|---|
| Issue date: | 09/24/2018 |
| From: | Tregoning R L NRC/RES/DE |
| To: | |
| Shared Package | |
| ML18267A083 | List: |
| References | |
| Download: ML18267A095 (5) | |
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© 2018 Electric Power Research Institute, Inc. All rights reserved.Gary L. StevensTechnical Executive, EPRINRC Public Meeting on Environmentally Assisted Fatigue (EAF) Research and Related ASME ActivitiesSeptember 25, 2018NRC Headquarters -Rockville, MDReview of Actions from June 30, 2016 Meeting 2© 2018 Electric Power Research Institute, Inc. All rights reserved.June 30, 2106 EAF MeetingThe last NRC EAF public meetingwas held on June 30, 2016The meeting summary is availablein ADAMS at ML16197A0237 presentations were made:1.EPRI Overview (ML16183A045)2.Testing (ML16183A099)3.Fatigue Usage Life and GradientFactors for ASME Class 1 PipingAnalyses (ML16183A066)4.Alternative Approaches for ASME Code Simplified Elastic-Plastic Analysis (ML16183A077)5.Fatigue Limit of Stainless Steel for Use in Vibration Evaluation (ML16183A084)6.Effects of Irradiation on Fatigue Life (ML16183A097)7.Environmentally-Assisted Fatigue Crack Growth in Irradiated Stainless Steels (ML16183A046) 3© 2018 Electric Power Research Institute, Inc. All rights reserved.Actions/Next Steps from Meeting (1/2)The following action items were identified during the meeting:a.Mr. Steininger of EPRI will provide the details of the analysis using the modified rate approach in NUREG/CR-6909 rev. 1 to predict the results of the complex strain transient tests conducted at MHISTATUS: b.Mr. Steininger of EPRI will determine if the factor on cycles was applied to the NUREG/CR-6909, rev 1 (draft) predictions of the complex strain transient tests conducted at MHISTATUS: c.Mr. Nathan Palm of EPRI will develop a strategy for implementing the life and gradient factor method within the ASME Code using a process that engenders early and frequent participation from NRC staffSTATUS: d.Dr. Ranganath of XGEN will revise the draft Code Case on alternative rules for simplified elastic-plastic analysis to ensure that it applies to both piping and reactor vessel componentsSTATUS: e.Dr. Ranganath of XGEN will determine if a draft Code Case for performing mean stress correction as a function of temperature would be more beneficial than simply using the method as the technical basis for supporting the use of the fatigue limit of 13.6 for stainless steels up to 343°C. Next, if appropriate, Dr. Ranganath will also develop a draft of such a Code CaseST ATUS: f.Mr. Palm of EPRI will ask Dr. Pathania of EPRI to provide a brief description of the plots comparing crack growth in LWR environments, both with and without irradiation, with crack growth rates in laboratory air. This description will identify how the loading conditions are relevant to fatigue and how the results demonstrate that FCGRs are increased by fatigue compared with constant load CGRsSTATUS: EAFCG in Irradiated SS.pdf 4© 2018 Electric Power Research Institute, Inc. All rights reserved.Actions/Next Steps from Meeting (2/2)The following action items were identified during the meeting (continued):g.Dr. Tregoning will arrange a meeting among NRC, EPRI, and DOE to discuss possible research to This report is planned for completion in December 2016STATUS: A meeting was not arranged. However, EPRI Report 3002007969 (not publicly considered writing an ASME PVP paper based on this final report, but did not do so because irradiated fatigue crack growth did not have high priority for the industry and funding was not available for the additional effort to do so. Work closely related to EPRI Report 3002007969 is publicly available in PVP Paper PVP2016-63640, Crack Tip Strain Rate Models for Environmentally-Assisted Fatigue Crack Growth in Light Water Reactor Environments, Proceedings of the ASME 2016 Pressure Vessels and Piping Conference, July 17-21, 2016, Vancouver, British Columbia, Canada. A brief description of this related work and relevant content is included in the file associated with the response to Item f. h.In concert with previous action item, the next in-depth meeting on fatigue activities will be planned by irradiation effects has been completedSTATUS: This meeting.i.Mr. Robin Dyle of EPRI will create a standing agenda item on metal fatigue to the quarterly call to discuss of NRC and industry activities related to materials issues. The objective of this agenda item is to provide a brief status on progress and identify the need and time-frame for future in-depth meetings on the topicSTATUS: EPRI discusses all significant materials issues during the quarterly call with NRC; significant fatigue-related issues.
5© 2018 Electric Power Research Institute, Inc. All rights reserved.