Occasional Topics
OTjapan Measures for Tsunami Striking Nuclear Power Station in Japan
Special Article: The Great Tohoku Earthquake (1)
OTjapan The Tragedy of “To Be” Principle in the Japanese Nuclear Industry
EJAMOT_CN3_Figure1_The_outside_view_of_CEFR OTChinaPlanning and Consideration on SFR R&D Activities in China
< All Occasional Topics

ICMST-Kobe 2014
Nov 2(Sun) - 5(Wed), 2014
Kobe, Japan
Nuclear Regulation Authority Outline of the New Safety Standards for Light Water Reactors for Electric Power Generation
For Public Comment
Outline of New Safety Standard (Design Basis)
For Public Comment
New Safety Standards (SA) Outline (Draft)
For Public Comment
Outline of New Safety Standard(Earthquake and Tsunami)(DRAFT)

Vol.6 No.1(May-25)
Vol.5 No.4(Feb-25)
Vol.5 No.3(Nov-25)
Vol.5 No.2(Aug-26)

< Other Issues

Featured Articles
EJAM6-1NT63 Double-arm Heavy Machinery-type Robot "ASTACO-SoRa"
EJAM6-1NT64 Quadruped Robot for Nuclear Facilities

(in English)


Vol.6 No.1 previous AA 74-SP11 (75-76)-Errata NT 63-64

Academic Articles
Regular Paper Vol.6 No.1 (2014) p.14 - p.23

Development of thermal fatigue evaluation methods of piping systems

Naoto KASAHARA1, Takamoto ITOH2, Masakazu OKAZAKI3, Yukihiko OKUDA4, Masayuki KAMAYA5, Akira NAKAMURA5, Hitoshi NAKAMURA6, Hideo MACHIDA7 and Masaaki MATSUMOTO8

1The University of Tokyo, School of Engineering, 7-3-1, Bunkyo-ku, Tokyo, 113-8656 Japan
2Ritsumeikan University
3Nagaoka University of Technology
4TOSHIBA Corporation
5Institute of Nuclear Safety System, Incorporated
6ITOCHU Techno-Solutions Corporation
7TEPCO Systems Corporation
8Mitsubishi Research Institute, Inc.

Nuclear piping has various kinds of thermal fatigue failure modes. Main causes of thermal loads are structural responses to fluid temperature changes during plant operation. These phenomena have complex mechanisms and many patterns, so that their problems still occur in spite of well-known issues. The guideline of the JSME (Japan Society of Mechanical Engineering) for estimation of thermal fatigue failures in piping system is employed as Japanese regulation. To improve this guideline, generation mechanisms of thermal load and fatigue failure have been investigated and summarized into the knowledgebase. And numerical simulation methods to replace experimental based methods were studied.
Furthermore, probabilistic failure analysis approach with main influence parameters was investigated to be applied for the plant system safety. Thus, based on the knowledge, estimation methods revised from the JSME guideline were proposed.

Fatigue, Thermal Stress, Thermal Hydraulics, Numerical Simulation, Piping, Nuclear Reactor Plant
Full Paper: PDF EJAM Vol.6No.1 pp.14-23 "Development of thermal fatigue evaluation methods of piping systems"

Article Information
Article history:
Received 23 December 2013
Accepted 7 May 2014