0
Research Papers: Materials and Fabrication

Estimates of Mechanical Properties and Residual Stress of Narrow Gap Weld for Leak-Before-Break Application to Nuclear Piping

[+] Author and Article Information
Jun-Seok Yang, Chi-Yong Park

Nuclear Power Laboratory, Korea Electric Power Research Institute, 65 Munji-ro, Yusung-gu, Daejeon 305-760, Korea

Nam-Su Huh1

School of Mechanical Design and Automation Engineering, Seoul National University of Technology, 172 Gongreung 2-dong, Nowon-gu, Seoul 139-743, Koreanam-su.huh@snut.ac.kr

1

Corresponding author.

J. Pressure Vessel Technol 133(2), 021403 (Mar 14, 2011) (7 pages) doi:10.1115/1.4002279 History: Received January 07, 2010; Revised July 06, 2010; Published March 14, 2011; Online March 14, 2011

The present paper addresses the mechanical characteristics of the stainless steel narrow gap weld (NGW) for the leak-before-break (LBB) application to the main loop piping of a nuclear power plant. Recently, in Korea, the connection with the reactor coolant main loop piping and the steam generator has been welded with ER308L NGW after the replacement of a steam generator of a Korean nuclear power plant. The NGW technique has many merits, for instance, the reduction of construction time and the reduction of shrinkage and deformation after welding due to its small groove angle and welding bead width compared with the conventional welds. In this paper, the tensile and fracture toughness test results of the three ER308L test coupons from NGW were presented and compared with those from conventional welds at the operating condition of the nuclear power plant. In addition, the distribution of the welding residual stress as well as the deformation behavior of the ER308L weld due to NGW was predicted through the nonlinear two-dimensional finite element analysis in which the detailed actual welding process of NGW was simulated. The results presented in this paper can be used to evaluate LBB application to nuclear piping with NGW and to provide the important information to perform the flaw evaluation as well as improve the weld procedure of NGW.

FIGURES IN THIS ARTICLE
<>
Copyright © 2011 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Type 304L test coupons welded by narrow gap weld

Grahic Jump Location
Figure 2

(a) Geometry of narrow gap weld employed in the present study and (b) schematic of welding bead sequence (mm)

Grahic Jump Location
Figure 3

Drawing of tensile test specimen (mm)

Grahic Jump Location
Figure 4

Drawing of fracture toughness test specimen (mm)

Grahic Jump Location
Figure 5

Drawing of cutting location of tensile and fracture toughness test specimen at test coupon (bird’s-eye view)

Grahic Jump Location
Figure 6

Drawing of cutting location of tensile and fracture toughness test specimen at test coupon (side view)

Grahic Jump Location
Figure 7

Photograph of 1T-C(T) specimen with notch along the centerline of weld

Grahic Jump Location
Figure 8

J-resistance curves for narrow gap weld at 316°C

Grahic Jump Location
Figure 9

Comparison of J-resistance curves of the ER308L NGW with those of SA312 TP316 welds and type 316 SAWs

Grahic Jump Location
Figure 10

Finite element mesh employed in the present study

Grahic Jump Location
Figure 11

Material properties with varying temperature. (a) Elastic modulus and (b) yield strength.

Grahic Jump Location
Figure 12

Distribution of welding residual stress due to NGW along the inner surface of pipe. (a) Axial stress and (b) hoop stress.

Grahic Jump Location
Figure 13

Distribution of welding residual stress due to NGW along the outer surface of pipe. (a) Axial stress and (b) hoop stress.

Grahic Jump Location
Figure 14

Distribution of welding residual stress due to NGW along the weld center line of pipe. (a) Axial stress and (b) hoop stress.

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