核电站控制棒导向筒组件半方管电子束焊缝熔深问题分析及改进运用

Analysis for penetration on electron beam weld for nuclear control rod guide tube assembly and process improvement application

某核电站控制棒导向筒组件半方管采用真空电子束焊接,焊缝经超声检测发现存在熔深不足的问题,通过对不同交货态及批次的原材料进行焊接对比试验,以及对影响焊缝熔深检测的可能因素进行研究分析,从降低半方管原材料中非金属氧化物形成的孔洞和钉尖缺陷对焊缝熔深的影响出发,采用电子束焊接重熔的方式,延长焊缝熔敷金属的高温停留时间,提高电子束流进行焊接修复和工艺改进,经工艺试验验证,有效地解决了焊缝熔深的问题,并在后续项目中成功推广运用。

Poor penetration was detected by ultrasonic testing on nuclear control rod guide tube assembly welded by electron beam welding.The welding contrast test on different batches of raw materials and other possible factors affecting the weld penetration were researched and analyzed.In order to reduce the effect of holes formed by non-metallic oxides and spiking defect in the raw material on weld penetration,the electron beam remelting process was used to prolong the high temperature residence time of weld deposit metal,and improve electron beam flow to conduct welding repair and process improvement.This method was verified by the process tests and can effectively solve the problem of weld penetration,and was successfully promoted and applied in follow-up projects.