Residual stresses of small-bore butt-welded piping measured by quantum beam hybrid method

量子ビームの相補利用による小径配管の応力測定

鈴木 賢治*; 三浦 靖史*; 豊川 秀訓*; 城 鮎美*; 菖蒲 敬久  ; 諸岡 聡  ; 柴山 由樹

Suzuki, Kenji*; Miura, Yasufumi*; Toyokawa, Hidenori*; Shiro, Ayumi*; Shobu, Takahisa; Morooka, Satoshi; Shibayama, Yuki

In this study, austenitic stainless steel pipes with a small diameter (100A) were butt-welded and the residual stress was measured using high energy synchrotron radiation X-rays and neutron. The welding residual stress is asymmetrical with respect to the welding line and has unevenness due to the crystal grains. Large axial residual stress occurs from the HAZ near the penetration bead toward the weld part. A simulation of a butt-welded pipe was performed using the finite element method. In the half model of the welded pipe, the butt-plane was assumed to keep a plane. The simulated residual stress by the half model was larger than that by the whole model. To perform an accurate simulation, the whole butt-welded piping must be modeled. The real tensile stress area from the HAZ near the penetration bead toward the weld was not obtained by the simulation.