Session: MF-04-01 Fitness-For-Service and Failure Assessment

Paper Number: 62845

Start Time: Tuesday, July 13, 2021, 09:00 AM

62845 - Progress of EASICS Validation Experiments and Code Comparison of R5, RCC-MRX and Asme Iii Division V 

The “Establishing AMR Structural Integrity Codes and Standards for UK GDA” (EASICS) project was established in 2019 to help support the acceptance of Advanced Modular Reactors, or AMRs, which are typically based on high temperature Generation IV reactors.  The EASICS project is looking to help define the requirements for codes and standards for the design of AMRs for use in the UK, to ensure that state-of-the art knowledge will be brought to bear on developing the required design and assessment methodologies.  The EASICS project started in July 2019 and is looking to complete by December 2021.

To support this, the work presented in this paper provides an overview of two interacting aspects of this programme. The first is to perform validation tests for high temperature creep-fatigue assessments of a plant relevant component.  The second aspect is to use these results, along with those of other identified tests, to provide a comparison of internationally recognised approaches for the assessment of high temperature (creep regime) components. This paper provides an update to the progress where an initial overview of the works was presented at the 2020 conference.

Specialist testing of a plant relevant component (thin tubes butt welded together) under high temperature loading conditions is underway with some initial results available. The validation testing includes both fatigue tests and creep-fatigue tests on 316H welded thin section tubes.  The tubes have been subjected to strain-controlled tension/compression (R-ratio of -1), with some including a displacement controlled dwell.  The tests will be conducted at 525°C.  An update to the progress of these tests is included herein.

To help enhance interaction with the code bodies, and to understand the impact of differences in the approaches, comparative assessments have also be performed when adopting R5, ASME Section III Div 5 and RCC-MRx.  One comparison will be based around the tests detailed here.  The second assessment comparison will consider the Evasion mock-up tests provided by CEA (sodium based thermal shock tests).  The third assessment case is loosely based around a plant relevant assessment within one of the UK Advanced Gas Reactors (AGRs).  This paper provides an overview of the results from these comparisons. 

The subsequent discussions over results, differences and potential impact to the codes will help inform a guidance document to best assess AMRs in the UK.

Presenting Author: Peter James Jacobs

Authors:

Peter James Jacobs
David Coon Jacobs
Colin Austin Jacobs
Nick Underwood National Nuclear Laboratory
Caroline Meek National Nuclear Laboratory
Marc Chevalier EDF Energy
David Dean EDF Energy