核电站低压缸爆破片异常破裂失效原因分析

Cause Analysis on Abnormal Rupture of LP Cylinder Rupture Disc of Nuclear Power Plant

针对某核电站低压缸大气释放阀爆破片(简称爆破片)装置异常破裂的情况,对爆破片失效特征等信息进行收集,结合低压缸运行工况,对爆破片进行了宏观裂纹分析、微观断口分析及材料成分分析,同时进行了材料力学性能试验、金相试验和爆破模拟试验。所得结果为:铅制低压缸爆破片断裂形式为疲劳断裂,断裂源自纯铅材料的蠕变敏感性。为此,提出了缩短更换爆破片年限的建议。

Data information is collected on the failure characteristics of abnormal rupture of the rupture disc of low-pressure （LP） cylinder release valve.In combination with the working conditions of LP cylinder,the macro crack analysis,microscopic fracture analysis and material composition analysis are conducted.Meanwhile,the mechanical performance test,metallurgical test and blast simulation test are also carried out.The results demonstrate that the crack of the lead-made rupture disc shall be categorized as fatigue fracture,resulting from the creep sensitivity of pure lead material.Therefore,suggestions such as shortening the replacing time interval of the rupture disc are put forward.