在至少运行了30年之后,Savannah River 厂对11套除氧器系统进行了检验。每套除氧器系统包括加热容器和水箱各一,在所有22台除氧器中,仅发现11只有裂纹,目前均已修复,在发现的裂纹中,长度方向尺寸最长达一英寸,既有垂直于焊缝的,也有平行于焊缝的,均尚未穿透。为了便于进行金相分析,已将焊缝取样。该项分析表明了一个非常明确的腐蚀机理,即在裂纹内部有一层极其致密的氧化物。检查了这些除氧器的运行方式和水化学工况,因为其中最多有4套是在同一动力房和在相同的运行工况下运行的。 After running at least 30 years, Savannah River’s 11 deaerator systems were tested. Each deaerator system consisted of a heating vessel and a water tank. In all 22 deaerators, only 11 cracks were found and are now repaired. In the cracks found, the length in the length direction is up to one inch in size. Both There are perpendicular to the weld, but also parallel to the weld, have not yet penetrated. In order to facilitate the metallographic analysis, the weld has been sampled. This analysis shows a very clear mechanism of corrosion, that is, an extremely dense oxide inside the crack. The operation of these deaerators and their hydrochemical conditions were checked as up to 4 of them were operated in the same power room and under the same operating conditions.