Nondestructive Evaluation of Welding Residual Stress in Power Plant Facilities Using Instrumented Indentation Technique

Abstract:

The weld joints in power-plant pipelines have long been considered important sites for safety and reliability assessment. In particular, the residual stress in pipeline weldments induced by the welding process must be evaluated accurately before and during service. This study reports an indentation technique for evaluating welding residual stress nondestructively. Indentation load-depth curves were found to shift with the magnitude and direction of the residual stress. Nevertheless, contact depths in the stress-free and stressed states were constant at a specific indentation load. This means that residual stress induces additional load to keep contact depth constant at the same load. By taking these phenomena into account, welding residual stress was obtained directly from the indentation load-depth curve. In addition, the results were compared with values from the conventional hole-drilling and saw-cutting methods.

• Periodical: Key Engineering Materials (Volumes 297-300)
• Pages: 2122-2127
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.297-300.2122
• Online since: November 2005
• Authors: Yeol Choi, Yun Hee Lee, Jae Il Jang, Sang Ki Park, Kwang Ho Kim, Yang Won Seo, Dong Il Kwon
• Keywords: Instrumented Indentation, Nondestructive Testing (NDT), Residual Stress, Welding

References

This article has no references.