摘要
针对一起500 kV断路器爆破片破裂事故,通过对破裂爆破片开展理化检验,发现故障爆破片材质为灰铸铁,表面有微孔,双侧用橡胶层密封保护,没有锈蚀,电镜分析表明材料脆性较大。通过更换同型断路器爆破片,比较新旧爆破片的性能,发现旧爆破片均有变形,大部分旧爆破片外侧橡胶层老化龟裂,导致爆破片进水锈蚀。通过开展爆破试验,发现部分旧爆破片爆破压力降低,但并不是锈蚀严重的样品。结果表明锈蚀并不是导致爆破片爆破压力下降的关键原因,该爆破片为平板型,铸铁材质,脆性较大,抗疲劳性能不足、表面有微孔缺陷是导致该起事故的根本原因。
In view of the burst of rupture disc for 500 kV circuit breaker,it is found through the physical and chemical inspection of the burst rupture disc that the material of the failed rupture disc is gray cast iron with microporous on the surface,with sealing and protection with rubber layers on both sides and without corrosion.Electron microscopy analysis shows that the material is of high brittleness.By replacing the rupture disc of the same type of circuit breaker and comparing the performance of the new and old rupture discs,it is found that the old rupture disc has deformation and the rubber layer of outer side of the most of old rupture discs is aged and cracked,causing water ingress and corrosion of rupture disc.Moreover,it is still found by the blasting test that the blasting pressure of some old rupture discs is reduced but not the samples with severe corrosion.The result shows the corrosion is not the key cause of the blasting pressure drop of the rupture disc.The rupture disc is of flat type and cast-iron material with high brittleness,insufficient fatigue resistance and microporous defects on the surface,which are the root cause of the failure.
作者
焦宗寒
郑欣
马宏明
宋玉锋
JIAO Zonghan;ZHENG Xin;MA Hongmin;SONG Yufeng(Yunnan Electric Power Research Institute,Yunnan Power Grid Co.,Ltd.,Kunming 650217,China)
出处
《高压电器》
CAS
CSCD
北大核心
2021年第12期225-231,共7页
High Voltage Apparatus
关键词
罐式断路器
爆破片
灰铸铁
失效分析
dead tank circuit breaker
rupture disc
gray cast iron
failure analysis
作者简介
通信作者:焦宗寒(1990-),男,硕士,工程师,目前从事电网重要部件失效分析、电气设备状态监测与故障诊断(E-mail:1207962456@qq.com)。
