Defect Assessment Procedure for Low to High Temperature Range

2003 ◽  
Author(s):  
Bilal Dogan ◽  
Robert Ainsworth
Keyword(s):  
High Temperature ◽  
Growth Conditions ◽  
Life Assessment ◽  
Assessment Procedure ◽  
High Temperature Range ◽  
Temperature Range ◽  
Defect Assessment ◽  
Creep Fatigue ◽  
Recent Developments ◽  
Assessment Procedures

There are many similarities between available procedures used for defect assessment. They have been developed as a result of experience gained from material-specific programs and have often been verified using the same data. One recently updated document covering life assessment procedures under creep and creep/fatigue crack growth conditions is BS 7910. This document takes into account some of the most recent developments in the subject, including some from the British Energy R5 Procedure. Future developments in defect assessment procedures will follow the route of simplified and unified codes covering defect behaviour in the low to high temperature range. In this paper, the relevance of the insignificant creep curves in RCC-MR for defect free structures and the creep exemption criteria in BS7910 are examined. Then, an overview is given of some European developments in defect assessment methods for Fitness-for-Service assessment, based on recent and current projects such as the EC thematic network FITNET.

Recent Developments in High Temperature Codes

2009 ◽  
Author(s):  
Bilal Dogan ◽  
R. A. Ainsworth
Keyword(s):  
High Temperature ◽  
Power Plants ◽  
Laboratory Data ◽  
Material Behavior ◽  
Life Assessment ◽  
Creep Fatigue ◽  
Recent Developments ◽  
The Subject ◽  
Static And Cyclic Loading ◽  
Assessment Procedures

The codes and standards specify design rules and methods for assessing defects in structures in service. Recent international effort on design and assessment of components subjected to quasi-static and cyclic loading at high temperatures has focused on the issue of Creep-Fatigue damage and condition assessment, which to date have not been comprehensively addressed in codes. The work has concentrated on basic understanding of material behavior and methods for analyzing laboratory data in order to address the need for service life assessment of components in ageing plants. This recognizes that power plants, on average 35 years in service, are facing increased operational demands imposed in order to respond to the increasing electricity demand. This paper gives an overview of the subject procedures and recent developments in codes and standards. Novel features of the procedure developments relative to the existing high temperature assessment procedures are highlighted.

scholarly journals High-Temperature Deformation of Naturally Aged 7010 Aluminum Alloy

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 581
Author(s):  
Abdulhakim A. Almajid
Keyword(s):  
Activation Energy ◽  
Aluminum Alloy ◽  
High Temperature ◽  
Threshold Stress ◽  
Activation Energies ◽  
Temperature Deformation ◽  
High Temperature Range ◽  
Temperature Range ◽  
True Activation Energy ◽  
Two Temperatures

This study is focused on the deformation mechanism and behavior of naturally aged 7010 aluminum alloy at elevated temperatures. The specimens were naturally aged for 60 days to reach a saturated hardness state. High-temperature tensile tests for the naturally aged sample were conducted at different temperatures of 573, 623, 673, and 723 K at various strain rates ranging from 5 × 10−5 to 10−2 s−1. The dependency of stress on the strain rate showed a stress exponent, n, of ~6.5 for the low two temperatures and ~4.5 for the high two temperatures. The apparent activation energies of 290 and 165 kJ/mol are observed at the low, and high-temperature range, respectively. These values of activation energies are greater than those of solute/solvent self-diffusion. The stress exponents, n, and activation energy observed are rather high and this indicates the presence of threshold stress. This behavior occurred as a result of the dislocation interaction with the second phase particles that are existed in the alloy at the testing temperatures. The threshold stress decreases in an exponential manner as temperature increases. The true activation energy was computed by incorporating the threshold stress in the power-law relation between the stress and the strain. The magnitude of the true activation energy, Qt dropped to 234 and 102 kJ/mol at the low and high-temperature range, respectively. These values are close to that of diffusion of Zinc in Aluminum and diffusion of Magnesium in Aluminum, respectively. The Zener–Hollomon parameter for the alloy was developed as a function of effective stress. The data in each region (low and high-temperature region) coalescence in a segment line in each region.

scholarly journals Creep Fatigue Life Assessment of a Pipe Intersection with Dissimilar Material Joint by Linear Matching Method

2016 ◽  
Vol 853 ◽  
pp. 366-371
Author(s):  
Daniele Barbera ◽  
Hao Feng Chen ◽  
Ying Hua Liu
Keyword(s):  
High Temperature ◽  
Fatigue Life ◽  
Direct Method ◽  
Life Assessment ◽  
Dissimilar Material ◽  
Matching Method ◽  
Fatigue Life Assessment ◽  
Creep Fatigue ◽  
The Impact ◽  
Linear Matching Method

As the energy demand increases the power industry has to enhance both efficiency and environmental sustainability of power plants by increasing the operating temperature. The accurate creep fatigue life assessment is important for the safe operation and design of current and future power plant stations. This paper proposes a practical creep fatigue life assessment case of study by the Linear Matching Method (LMM) framework. The LMM for extended Direct Steady Cycle Analysis (eDSCA) has been adopted to calculate the creep fatigue responses due to the cyclic loading under high temperature conditions. A pipe intersection with dissimilar material joint, subjected to high cycling temperature and constant pressure steam, is used as an example. The closed end condition is considered at both ends of main and branch pipes. The impact of the material mismatch, transitional thermal load, and creep dwell on the failure mechanism and location within the intersection is investigated. All the results demonstrate the capability of the method, and how a direct method is able to support engineers in the assessment and design of high temperature component in a complex loading scenario.

Method for extending the scale of a radiation pyrometer to the high-temperature range

1965 ◽  
Vol 8 (10) ◽  
pp. 963-965
Author(s):  
L. M. Golub ◽  
V. E. Finkel'shtein ◽  
E. S. Shpigel'man
Keyword(s):  
High Temperature ◽  
Radiation Pyrometer ◽  
High Temperature Range ◽  
Temperature Range

RCC-MRx Appendix A16 Methodology for the Analytical J Calculation Under Thermal and Combined Thermal + Mechanical Loadings for Pipes and Elbows and Related Assessment Tool MJSAM

2011 ◽  
Author(s):  
S. Marie ◽  
M. Ne´de´lec ◽  
C. Delaval
Keyword(s):  
Nuclear Power ◽  
Assessment Tool ◽  
Analytical Calculation ◽  
Large Set ◽  
Microsoft Excel ◽  
Defect Assessment ◽  
Initiation And Propagation ◽  
Creep Fatigue ◽  
Assessment Procedures ◽  
2D And 3D

RCC-MRx code provides flaw assessment methodologies and related tools for Nuclear Power Plant cracked components. An important work has been made in particular to develop a large set of compendia for the calculation of the parameter J for various components (plates, pipes, elbows,…) and various defect geometries. Also, CEA in the frame of collaborations with IRSN, developed a methodology for J analytical calculation for cracked pipes and elbows submitted to thermal and combined mechanical and thermal loadings. This paper presents first the development of this methodology and an overview of the validation strategy, based on reference 2D and 3D F.E. calculations. The second part of the paper presents the last version of the MJSAM tools which is based on the 2010 version of the appendix A16 of the RCC-MRx code. All compendia (for KI, J and C* calculation) and all defect assessment procedures have been implemented in the tool: It covers crack initiation and propagation under fatigue, creep, creep-fatigue and ductile tearing situations. Sensitivity and probabilistic analyses can also been performed with this tool, directly linked to Microsoft Excel software for the results exploitation.

Development of Red Mud Coated Catalytic Filter for NOx Removal in the High Temperature Range of 300–450 °C

2019 ◽  
Vol 150 (3) ◽  
pp. 702-712 ◽  
Author(s):  
Lin Huangfu ◽  
Abdullahi Abubakar ◽  
Changming Li ◽  
Yunjia Li ◽  
Chao Wang ◽  
...  
Keyword(s):  
High Temperature ◽  
Red Mud ◽  
Nox Removal ◽  
High Temperature Range ◽  
Temperature Range ◽  
Catalytic Filter

Synthesis, structure and temperature sensing of a lanthanide-organic framework constructed from a pyridine-containing tetracarboxylic acid ligand

CrystEngComm ◽  
2018 ◽  
Vol 20 (45) ◽  
pp. 7395-7400 ◽  
Author(s):  
Dian Zhao ◽  
Huizhen Wang ◽  
Guodong Qian
Keyword(s):  
High Temperature ◽  
Metal Organic Framework ◽  
Temperature Sensing ◽  
Tetracarboxylic Acid ◽  
High Temperature Range ◽  
Temperature Range ◽  
Acid Ligand ◽  
Metal Organic ◽  
Lanthanide Metal ◽  
Organic Framework

A high sensitive, thermostable mixed lanthanide metal–organic framework, Eu0.19Tb0.81PDDI, was developed as a self-calibrated thermometer effective in the high temperature range of 313 to 473 K.

The autoignition of iso-dodecane in low to high temperature range: An experimental and modeling study

2019 ◽  
Vol 210 ◽  
pp. 222-235 ◽  
Author(s):  
Yebing Mao ◽  
Yuan Feng ◽  
Zhiyong Wu ◽  
Sixu Wang ◽  
Liang Yu ◽  
...  
Keyword(s):  
High Temperature ◽  
High Temperature Range ◽  
Temperature Range ◽  
Modeling Study
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