控制棒驱动机构现场安装OMEGA焊缝坡口缺陷返修试验研究

Experiment on repair of OMEGA weld groove defects for CRDM site welding

针对控制棒驱动机构现场安装OMEGA焊缝坡口缺陷进行了返修试验。试验结果表明,矫形后的坡口区域微观金相组织与其他区域的母材金相组织相比较未出现异常,未观察到矫形后的金属有冷作硬化的痕迹。模拟焊接后的焊接接头,外观成形良好,焊缝宽度适中,满足设计要求。焊缝组织为正常的奥氏体加少量铁素体,与未返修区域的焊缝组织一致。全部检测结果证明,返修方案正确可靠,便于实施。该试验结果为同类CRDM管座坡口损伤问题的处理提供了成功的经验。

The experiments were performed for repairing the defects of OMEGA weld groove in CRDM site welding.The results show that,compared with the structure of the zone without shape-righting,there is no abnormality for micrographic structure of the shape-righted zone,and there is also no evidence of cold hardening in this zone.In this repair test,the weld with shape-righted groove is performed as normal.After welding,the weld appearance is good,and the weld width is appropriate and satisfies the specification requirements.The structure of shape-righted zone is normal austenite with a little ferrite,the same as the zone without shaperighting.Since all the tests are qualified,the repair method is feasible and convenient to apply.It is a successful experience to deal with the same kind of defects for CRDM OMEGA weld.