実機プラントの炉心シュラウドへのウォータージェットピーニング（WJP）適用とWJP施工後の残留応力測定
Application of Water Jet Peening to the Shroud Components in BWR Power Plant and Residual Stress Measurement after WJP.
著者:
大城戸 忍 Shinobu OKIDO 椿 正昭 Masaaki TSUBAKI 千葉 篤志 Atsushi CHIBA 佐川 渉 Wataru SAGAWA 松田 徹 Toru MATSUDA
発刊日:
公開日:
Nuclear Power PlantReactor Internal ComponentsResidual StressShroudWater Jet Peening(WJP)WeldX-ray Stress Measurement
概要
Residual stress improvement technologies have been developed and applied to Boiling Water Reactor (BWR) plant components in order to prevent from stress corrosion cracking (SCC) of stainless steel and Ni-based alloy materials. Water Jet Peening (WJP) is one of the effective procedures for residual stress improvement, and has the various advantages for the application to the reactor internal components of the operating nuclear power plants because WJP uses only water for residual stress improvement. As the results, WJP has been applied to 14 BWR plants so far. WJP was applied to the shroud components for the newly constructed plant, and the effects of WJP on the residual stresses of the actual power plant components were measured and evaluated directly and non-destructively by x-ray diffraction method. All of the residual stresses of the WJP-treated surface were compressive, and those values were almost the same as the mock-up test results executed before application to the actual components. These results demonstrate the effectiveness of WJP as one of the preventive maintenance technologies for SCC by producing the compressive residual stresses on the material surface.
