0
Research Papers: Materials and Fabrication

Failure Behavior of Multiple-Axial Part-Through-Wall Flaws in Alloy 690TT Steam Generator Tubes

[+] Author and Article Information
Ki Hyeon Eom

Department of Nuclear Engineering,
Chosun University,
309 Pilmun-daero,
Dong-Gu, Gwangju 61452, South Korea

Jin Weon Kim

Department of Nuclear Engineering,
Chosun University,
309 Pilmun-daero,
Dong-Gu, Gwangju 61452, South Korea
e-mail: jwkim@chosun.ac.kr

Yun Jae Kim

Department of Mechanical Engineering,
Korea University,
145 Anam-ro,
Seongbuk-Ku, Seoul 136-701, South Korea

Jong Sung Kim

Department of Mechanical Engineering,
Sunchon National University,
255 Jungang-ro,
Suncheon, Jeollanam-do 540-950, South Korea

1Corresponding author.

Contributed by the Pressure Vessel and Piping Division of ASME for publication in the JOURNAL OF PRESSURE VESSEL TECHNOLOGY. Manuscript received August 2, 2015; final manuscript received September 5, 2015; published online November 19, 2015. Assoc. Editor: Haofeng Chen.

J. Pressure Vessel Technol 138(2), 021406 (Nov 19, 2015) (10 pages) Paper No: PVT-15-1175; doi: 10.1115/1.4031663 History: Received August 02, 2015; Revised September 05, 2015

This study investigates the interaction effect of multiple-axial part-through-wall (PTW) flaws on the failure behavior of Alloy 690TT steam generator (SG) tubes. Burst tests of tubes with single and multiple flaws were conducted at room temperature (RT). The flaws were made by the electrodischarge machining (EDM) method on the outer surface of the specimens. Six different configurations of multiple flaws were considered to see the interaction effect; two and three collinear, two and three parallel, and two and three nonaligned flaws. In all cases, an axial flaw with a constant depth of 50% wall-thickness was considered, and the following variables were systematically varied; the axial and/or circumferential separating ligament lengths between flaws, the flaw length, and the number of flaws. Effects of these variables on the failure pressure and failure mode were investigated based on experimental data. The effects of separating ligament lengths and flaw lengths on the failure pressure were dependent on the type of flaw configuration. For collinear and nonaligned flaws, the decrease in failure pressure by the interaction of multiple flaws became significant as the number of flaws increased. The failure mode of multiple flaws was strongly dependent on the length of the flaws.

FIGURES IN THIS ARTICLE
<>
Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

USNRC, 1976, “ Bases for Plugging Degraded PWR Steam Generator Tubes,” U.S. Nuclear Regulatory Commission, Washington, DC, Regulatory Guide 1.121.
ASME, 1998, “ Rules for In-Service Inspection of Nuclear Power Plant Components,” ASME Boiler and Pressure Vessel Code, Sec. XI, American Society of Mechanical Engineers, New York.
MacDonald, P. E. , Shah, V. N. , Ward, L. W. , and Ellison, P. G. , 1996, “ Steam Generator Tube Failures,” U.S. Nuclear Regulatory Commission, Washington, DC, Report No. NUREG/CR-6365.
IAEA, 2011, “ Assessment and Management of Aging of Major Nuclear Power Plant Components Important to Safety: Steam Generator,” International Atomic Energy Agency, Vienna, Austria, Report No. IAEA-TECDOC-1668.
Shah, V. N. , and MacDonald, P. E. , 1993, Aging and Life Extension of Major Light Water Reactor Components, Elsevier, Amsterdam.
Lee, K. H. , Kim, H. D. , Kang, Y. S. , Nam, M. W. , and Cho, N. C. , 2014, “ Burst Pressure Tests of Axial Notched Steam Generator Tubes,” Trans. Korean Soc. Pres. Ves. Piping, 10(1), pp. 56–63.
Majumdar, S. , 1999, “ Prediction of Structural Integrity of Steam Generator Tubes Under Severe Accident Conditions,” Nucl. Eng. Des., 194(1), pp. 31–55. [CrossRef]
USNRC, 2002, “ Validation of Failure and Leak-Rate Correlations for Stress Corrosion Cracks in Steam Generator Tubes,” U.S. Nuclear Regulatory Commission, Washington, DC, Report Nos. NUREG/CR-6774 and ANL-01/34.
Hwang, S. S. , Kim, H. P. , and Kim, J. S. , 2004, “ Evaluation of the Burst Characteristics for Axial Notches on SG Tubings,” Nucl. Eng. Des., 232(2), pp. 139–143. [CrossRef]
Moon, S. I. , Chang, Y. S. , Kim, Y. J. , Lee, J. H. , Song, M. H. , and Choi, Y. H. , 2007, “ Determination of Failure Pressure for Tubes With Two Non-Aligned Through-Wall Cracks,” Int. J. Fract., 144(2), pp. 91–101. [CrossRef]
Shin, K. I. , Yoon, K. B. , and Park, J. H. , 2013, “ Experimental and Numerical Study on the Burst Pressure of Steam Generator Tubes With L- and U-Type Through-Wall Combination Cracks,” J. Mech. Sci. Technol., 27(8), pp. 2299–2304. [CrossRef]
Moon, S. I. , Chang, Y. S. , Kim, Y. J. , Lee, J. H. , Song, M. H. , Choi, Y. H. , and Kim, J. S. , 2006, “ Determination of Global Failure Pressure for Tubes With Two Parallel Cracks,” Fatigue Fract. Eng. Mater. Struct., 29(8), pp. 623–631. [CrossRef]
USNRC, 2002, “ Results From Pressure and Leak-Rate Testing of Laboratory-Degraded Steam Generator Tubes,” U.S. Nuclear Regulatory Commission, Washington, DC, Report Nos. NUREG/CR-6789 and ANL-01/31.
USNRC, 2009, “ Steam Generator Tube Integrity Issues: Pressurization Rate Effect, Failure Maps, Leak Rate Correlation Models, and Leak Rates in Restricted Areas,” U.S. Nuclear Regulatory Commission, Washington, DC, Report Nos. NUREG/CR-6879 and ANL-05/16.
ASTM, 2009, “ Standard Test Methods for Tension Testing on Metallic Materials,” ASTM International, West Conshohocken, PA, Standard No. ASTM E8/E8M - 09.
EPRI, 1991, “ Belgian Approach to Steam Generator Tube Plugging for Primary Water Stress Corrosion Cracking,” Electric Power Research Institute, Palo Alto, CA, Report No. EPRI NP-6626-SD.
EPRI, 2001, “ Effect of Pressurization Rate on Degraded Steam Generator Tubing Burst Pressure: Revision 1,” Electric Power Research Institute, Palo Alto, CA, Report No. EPRI 1006252.
Hernalsteen, P. , 1992, “ The Influence of Testing Conditions on Burst-Pressure Assessment for Inconel Tubing,” Int. J. Pressure Vessels Piping, 52(1), pp. 41–57. [CrossRef]
KHNP, 2013, “ Development of Technologies for Improving Integrity of Axial ODSCC in OPR1000 Steam Generator Tubes,” Korea Hydro & Nuclear Power Co., Seoul, Report No. TR-A10TX10.
EPRI, 2001, “ Steam Generator Degradation Specific Management Flaw Handbook,” Electric Power Research Institute, Palo Alto, CA, Report No. EPRI 1001191.
EPRI, 1991, “ Steam Generator Tube Integrity Volume 1: Burst Test Results and Validation of Rupture Criteria (Framatoms Data),” Electric Power Research Institute, Palo Alto, CA, Report No. EPRI NP-6865-L.

Figures

Grahic Jump Location
Fig. 1

SG tube specimens used for the experiment: (a) dimensions of SG tube specimen and (b) configurations of multiple PTW flaws

Grahic Jump Location
Fig. 2

Schematic diagram of test apparatus

Grahic Jump Location
Fig. 3

A sample of pressure versus time data for a SG tube specimen with multiple-axial PTW flaws

Grahic Jump Location
Fig. 4

Normalized failure pressures of SG tube specimens with a single-axial PTW flaw

Grahic Jump Location
Fig. 5

Normalized failure pressures of SG tube specimens with collinear axial multiple PTW flaws

Grahic Jump Location
Fig. 6

Normalized failure pressures of SG tube specimens with parallel multiple-axial PTW flaws

Grahic Jump Location
Fig. 7

Normalized failure pressures of SG tube specimens with nonaligned multiple-axial PTW flaws

Grahic Jump Location
Fig. 8

Effect of number of multiple-axial PTW flaws on the failure pressures of SG tube specimens: (a) collinear flaws and (b) nonaligned flaws

Grahic Jump Location
Fig. 9

Post-test photographs of SG tube specimens with a single-axial PTW flaw

Grahic Jump Location
Fig. 10

Post-test photographs of SG tube specimens with collinear and nonaligned multiple-axial PTW flaws: (a) collinear flaws and (b) nonaligned flaws

Grahic Jump Location
Fig. 11

Post-test photographs of SG tube specimens with parallel multiple-axial PTW flaws

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In