Inherent-Strain-Based Theory of Measurement of Three-Dimensional Residual Stress Distribution and Its Application to a Welded Joint in a Reactor Vessel

Author:

Nakacho Keiji1,Ogawa Naoki2,Ohta Takahiro3,Nayama Michisuke4

Affiliation:

1. Joining and Welding Research Institute, Osaka University, Mihogaoka 11-1, Ibaraki City, Osaka 567-0047, Japan e-mail:

2. Takasago Research & Development Center, Technology & Innovation Headquarters, Mitsubishi Heavy Industries, Ltd., 1-1 Shinhama, 2-chome, Arai-cho, Takasago City, Hyogo 676-8686, Japan e-mail:

3. Nagasaki Research & Development Center, Technology & Innovation Headquarters, Mitsubishi Heavy Industries, Ltd., 717-1, Fukahori-machi, 5-chome, Nagasaki City, Nagasaki 851-0392, Japan e-mail:

4. Technology & Innovation Headquarters, Mitsubishi Heavy Industries, Ltd., 16-5 Konan 2-chome, Minato-ku, Tokyo 108-8215, Japan e-mail:

Abstract

The stress that exists in a body under no external force is called the inherent stress. The strain that is the cause (source) of this stress is called the inherent strain. This study proposes a general theory of an inherent-strain-based measurement method for the residual stress distributions in arbitrary three-dimensional bodies and applies the method to measure the welding residual stress distribution of a welded joint in a reactor vessel. The inherent-strain-based method is based on the inherent strain and the finite element method. It uses part of the released strains and solves an inverse problem by a least squares method. Thus, the method gives the most probable value and deviation of the residual stress. First, the basic theory is explained in detail, and then a concrete measurement method for a welded joint in a reactor vessel is developed. In the method, the inherent strains are unknowns. In this study, the inherent strain distribution was expressed with an appropriate function, significantly decreasing the number of unknowns. Five types of inherent strain distribution functions were applied to estimate the residual stress distribution of the joint. The applicability of each function was evaluated. The accuracy and reliability of the analyzed results were assessed in terms of the residuals, the unbiased estimate of the error variance, and the welding mechanics. The most suitable function, which yields the most reliable result, was identified. The most reliable residual stress distributions of the joint are shown, indicating the characteristics of distributions with especially large tensile stress that may produce a crack.

Publisher

ASME International

Subject

Mechanical Engineering,Mechanics of Materials,Safety, Risk, Reliability and Quality

Reference15 articles.

1. Review of Stress Corrosion Cracking of Alloys 182 and 82 in PWR Primary Water Service (MRP-220),2007

2. Development and Experimental Validation of the Deep Hole Method for Residual Stress Measurement;J. Strain Anal. Eng. Des.,1996

3. Residual Stress Measurement by Successive Extension of a Slot: The Crack Compliance Method;Appl. Mech. Rev.,1999

4. A New Measuring Method of Residual Stresses With the Aid of Finite Element Method and Reliability of Estimated Values;J. Soc. Nav. Archit. Jpn.,1975

5. Fundamental Concept in Measurement of Residual Stresses Based on Finite Element Method and Reliability of Estimated Values;Theor. Appl. Mech.,1977

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