Results of EC FP7 Structural Performance of MULTI-METAL Component Project: Dissimilar Metal Welds Fracture Resistance Investigation

2015 ◽  
Author(s):  
Heikki Keinänen ◽  
Elisabeth Keim ◽  
Paivi Karjalainen-Roikonen ◽  
Sébastien Blasset ◽  
Philippe Gilles ◽  
...  
Keyword(s):  
Austenitic Steel ◽  
Structural Integrity ◽  
Good Practice ◽  
Research Centre ◽  
Joint Research ◽  
Integrity Assessment ◽  
Dissimilar Metal ◽  
Practice Approach ◽  
Stefan Institute ◽  
Assessment And Testing

The purpose of this paper is to disseminate the results of an EURATOM project MULTI-METAL focusing on the structural integrity assessment of dissimilar metal welds. The project started in February 2012 and ended in February 2015. The project is coordinated by VTT with 10 partner organizations from Europe : Technical Research Centre of Finland, Finland (VTT) – Coordinator, AREVA NP, France and Germany (ANP), Commissariat à l’Énergie Atomique et aux energies alternatives, France (CEA), Joint Research Centre of the European Commission, Belgium (JRC), EdF-Energy, United Kingdom (BE), Bay Zoltán Foundation for Applied Research, Hungary (BZF), Electricité de France, France (EDF), TECNATOM, Spain (TEC), Jožef Stefan Institute, Slovenia (JSI), Studsvik Nuclear AB, Sweden (STU). The underlying aim of the project is to provide recommendations for a good practice approach for the integrity assessment (especially testing) of tough dissimilar metal welds as part of overall ductile integrity analyses; this has been presented in the project overview [1]. Experience on typical DMWs concerning manufacturing, residual stresses, flaw assessment and testing have been reviewed. The specimens were taken from mock-ups of welded plates. Three DMWs design variants have been covered: narrow gap DMW with Ni-52, DMW with austenitic steel buttering and a DMW with Nienriched austenitic steel buttering. Mechanical characterization and fracture mechanics testing (CT, SEN(B) and SEN(T) specimens) have been performed. Interpretation of the test has required numerical analysis since the standard ASTM E1820 [2] (CT, SEN(B)) and guidelines dealing with SEN(T) [3][4] are not directly intended to cover DMW. The motivation of the project and its results are generally presented and discussed.

EC FP7 Structural Performance of MULTI-METAL Component: Project Overview

2013 ◽  
Author(s):  
Paivi Karjalainen-Roikonen ◽  
Elisabeth Keim ◽  
Philippe Gilles ◽  
Sébastien Blasset
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Structural Integrity ◽  
Good Practice ◽  
Research Centre ◽  
Resistance Testing ◽  
Joint Research ◽  
Text Book ◽  
Integrity Assessment ◽  
Dissimilar Metal

The purpose of this paper is to introduce a new EUROATOM project focusing on the structural integrity assessment of dissimilar metal weld. The project started in February 2012 and will last 3 years. The project is coordinated by VTT with 10 partner organizations from Europe: Technical Research Centre of Finland, Finland (VTT) - Coordinator AREVA NP, France and Germany (ANP) Commissariat à l’Énergie Atomique et aux energies alternatives, France (CEA) Joint Research Centre of the European Commission, Belgium (JRC) EdF-Energy, United Kingdom (BE) Bay Zoltán Foundation for Applied Research, Hungary (BZF) Electricité de France, France (EDF) TECNATOM, Spain (TEC) Jožef Stefan Institute, Slovenia (JSI) Studsvik Nuclear AB, Sweden (STU). Within MULTIMETAL, the main objectives are: - Develop a codification for fracture resistance testing in multi-metal specimens. - Develop harmonized procedures for dissimilar metal welds integrity assessment. The underlying aim of the project is to provide recommendations for a good practice approach for the integrity assessment (especially testing) of dissimilar metal welds as part of overall integrity analyses including leak-before-break (LBB) procedures. The project will promote the development of a common understanding for structural integrity assessment of dissimilar metal welds (DMWs) in existing and future nuclear power plants (NPPs) in EU member states. It will provide the technical basis for the development of harmonized European codification for multi-metal components, which is currently non-existing. A trainee program will be finally developed and text book as well as learning materials will be issued. The project will interact with the European Network of Excellence NULIFE and NUGENIA.

Residual Strain Measurement of C/C-SiC Tubes at High Temperature

2006 ◽  
Vol 524-525 ◽  
pp. 665-670 ◽  
Author(s):  
Robert C. Wimpory ◽  
Carsten Ohms ◽  
P. Horňák ◽  
Dimitar Neov ◽  
Anastasius Youtsos
Keyword(s):  
High Temperature ◽  
Neutron Diffraction ◽  
Residual Strain ◽  
Strain Measurement ◽  
Structural Integrity ◽  
Research Centre ◽  
Vacuum Furnace ◽  
Joint Research ◽  
Integrity Assessment ◽  
Residual Strains

As part of the European project “high and ultrahigh temperature heat exchangers” (HITHEX) the prediction and experimental assessment of the lifetime behaviour, characterisation and qualification of particular CMC materials, including carbon fibre reinforced carbonsiliconcarbides (C/C-SiC), has been executed. Part of the programme of the HITHEX project was the measurement of the strain development within the C/C-SiC tubular specimens from room to high temperature, the results of which are presented here. Residual strains have been determined in several specimens by neutron diffraction at the High Flux Reactor (HFR) of the Joint Research Centre in Petten, The Netherlands. At the HFR two facilities are available for residual strain investigations. Both instruments were utilised in the investigations. The first facility at beam tube HB5, the combined stress and powder diffractometer, employs a constant neutron wavelength of 0.257 nm, and the second facility at HB4, the Large Component Neutron diffraction facility, LCNDF, has a flexible wavelength. The installation of a vacuum furnace has enabled the residual strain measurement of specimens at high temperature on HB4. The furnace had to fulfil three main criteria for the investigation of these specimens; high-temperature, good neutron penetration and negligible oxidation of the specimens. The ceramic specimens, which have outer and inner diameters of 50 and 40 mm, respectively, and a length of 100 mm have been measured to temperatures of up to 1450°C. Measurements were carried out in two directions on the SiC phase of several specimens, i.e. in the radial and tangential (hoop) directions. The implications of these results with respect to the structural integrity assessment of these components at high temperatures are discussed.

Overview of Recent NUGENIA Activities Particularly in Relation to Structural Integrity

2015 ◽  
Author(s):  
John Sharples ◽  
Elisabeth Keim
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Structural Integrity ◽  
Nuclear Research ◽  
Joint Research ◽  
Non Profit ◽  
Integrity Assessment ◽  
Industry Research ◽  
Implementation And Dissemination ◽  
Technical Area

NUGENIA, an international non-profit association founded under Belgian legislation and launched in March 2012, is dedicated to nuclear research and development (R&D) with a focus on Generation II and III power plants. NUGENIA is the integrated framework between industry, research and safety organisations for safe, reliable and competitive nuclear power production, and is aimed at running an open innovation marketplace, to promote the emergence of joint research and to facilitate the implementation and dissemination of R&D results. The technical scope of NUGENIA consists of eight technical areas. One of these areas, Technical Area 4, is associated with the structural integrity assessment of systems, structures and components. A brief overview of recent NUGENIA activities in general is provided in this paper and a specific focus is given on developments in relation to Technical Area 4.

Standardisation on Measurement and Interpretation of Residual Stress Data

2019 ◽  
Author(s):  
Ali Mirzaee-Sisan ◽  
P. John Bouchard ◽  
Foroogh Hosseinzadeh
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Practice Guidelines ◽  
Structural Integrity ◽  
Good Practice ◽  
Critical Assessment ◽  
Numerical Prediction ◽  
Specific Technique ◽  
Integrity Assessment

Abstract This paper highlights many unanswered questions relating to the characterisation of residual stresses in weldments and their treatment in engineering critical assessment and fitness for service assessment codes and standards. The need for an overarching standardisation framework is identified which goes beyond developing good practice guidelines for numerical prediction or measurement using a specific technique. The framework should cover all uncertainties and possible errors in measuring, simulating and interpreting residual stress in the context of structural integrity assessment.

German Engineering Methods for Critical Crack Size Assessment in Ductile Regime Based on Envelop Flow Stress

2010 ◽  
Author(s):  
Se´bastien Blasset ◽  
Ralf Tiete ◽  
Elisabeth Keim
Keyword(s):  
Flow Stress ◽  
Structural Integrity ◽  
Base Material ◽  
Limit Load ◽  
Crack Size ◽  
Experimental Investigations ◽  
Critical Crack ◽  
Experimental Database ◽  
Integrity Assessment ◽  
Dissimilar Metal

The purpose of this paper is to present engineering methods used in Germany for integrity assessment of structural components with a flaw in the ductile regime. The methods are validated by more than 1500 experiments and cover through wall crack as well as part-through wall cracks (in either axial or circumferential orientation) located in base material, heat affected zone, homogeneous or dissimilar metal welds. By fulfilling the toughness requirement, the structural integrity of a cracked component in the ductile regime can be assessed conservatively (safely) by considering simplified methods for which only strength and impact energies values are needed. The physical and mathematical background of the methods for circumferential cracks (flow stress concept FSC; plastic limit load PLL) and for axial cracks (Battelle approach BMI; Ruiz approach RUIZ), as well as the historical connection with the German basis safety concept will be reviewed. Similarity with other international methods (like R6, Section XI of ASME Code, SRP 3.6.3) will be emphasized. The range of validity resulting from experimental investigations (experimental database built from own research or from literature) is summarized and the validation procedure of the methods (FSC, PLL, BMI, RUIZ) is explained. The resulting correction factors on flow stress (envelop flow stress) to account for elastic-plastic fracture conditions and to result in conservative (safe) predictions of crack instability depending on the method (FSC, PLL, BMI, RUIZ), crack orientation (circumferential and axial) and type of material (ferritic and austenitic) is given. The ratio of the computed experimental to the theoretical stress gained by these several engineering methods (German flow stress based simplified methods and other international methods) will be presented on the basis of the experimental database (with a various combination of geometry, materials and loading combination) which covers also elbows and vessels. Recommendations on the good use of the methods for ductile integrity assessment are given including also dissimilar metal welds consideration.

Good Practice Handbook for PTS Evaluation (Result of the IAEA Co-Ordinated Project on PTS)

2009 ◽  
Author(s):  
Vladislav Pistora ◽  
Milan Brumovsky ◽  
Nigel Taylor
Keyword(s):  
Thermal Shock ◽  
Best Practice ◽  
Structural Integrity ◽  
Good Practice ◽  
Pressure Vessels ◽  
Research Project ◽  
Integrity Assessment ◽  
Pressurized Thermal Shock ◽  
Sensitivity Studies ◽  
Reactor Pressure

Integrity and lifetime of reactor pressure vessels are practically determined by their behavior during “pressurized thermal shock” (PTS) emergency regimes as the most severe regimes during reactor operation. Assessment of these potential regimes is carried out mostly in deterministic way but used procedures are different in different countries. Proper and reliable evaluation of these PTS regimes depends on many parameters and approaches used during computations. During the period 2005 – 2008, the Coordinated Research Project 9 (CRP 9) “Review and Benchmark of Calculation Methods for Structural Integrity Assessment of RPVs During PTS” was organised by the IAEA. The overall objective of this Coordinated Research Project was to perform benchmark deterministic calculations of a typical pressurised thermal shock (PTS) regime and finally to recommend the best practice for PTS assessment. This paper describes main results and collected experience within this project that were bases for the preparation of the “Good Practice Handbook for Deterministic Evaluation of the Integrity of a Reactor Pressure Vessel during a Pressurised Thermal Shock” that will be issued as an IAEA TECDOC. Main parameters discussed in this handbook are: - selection of overcooling sequences; - thermal-hydraulics analyses; - temperature and stress field calculations; - crack tip loading incl.K estimations; - integrity assessment; - analyses of nozzles; - national practices; - results from sensitivity studies. Finally, recommendations for reliable and correct PTS evaluation are given.

Sign in / Sign up

Export Citation Format

Share Document