核容器环带区裂缝热荷载下的应力强度因子

计算了核容器环带区裂缝在热梯度荷载下的应力强度因子（ＳＩＦ）．结果是可靠的。 证实了快速变化温度场下的应力强度因子较稳态时为低的论断，并对可能出现的稳态温 度场进行ＳＩＦ的计算考查，确定了环带区最大假想裂缝在热荷载下的ＳＩＦ上限值， 这对核容器的缺陷评定有重要意义，扩大了评定公式的使用范围。文章指出：焊接研究 委员会第 １７５号公报（ＷＲＣ Ｂｕｌｌｅｔｉｎ １７５／Ａｕｅｕｓｔ，１９７２）中所给的热梯度应力强度因 子的近似公式是错误的．

Stress Intensity Factor at Beltline Flaws of Nuclear Reactor Pressure Vessel under Thermal Load

The paper gives a detailed computation of the stress intensity factor (SIF) at the maximum postulated beltline flaw of nuclear reactor pressur vessel under thermal gradient load with reliable results- It has been verified that the SIF due to the rapid temperature change is much lower than that in steady state. Also inspects the SIF in all possible steady temperature field and determines its upper bound value at the maximum postulated beltline flaw. The above result has significance to the flaw assessment of nuclear reactor pressure vessel, because it expands the scope of assessment. The author points out the fact that the approximate formula of SIF under thermal gradient load given in WRC 175 Bulletin is not correct and correction is made in this paper.