核电厂围板螺栓裂纹的失效分析与超声检测

Failure Analysis and Ultrasonic Testing of the Baffle Bolts Crack of Nuclear Power Plant

围板螺栓是反应堆堆芯内部结构的重要部件,由于其带有紧固销,因此实施超声检测时接触部位结构复杂,限制了超声波探头的接触耦合性。为了实现螺栓螺纹的反射信号和螺栓肩部缺陷信号的检出,对围板螺栓采用创新的探头设计和信号分析方法。采用检验系统对真实螺栓进行过盲测,结果显示检测灵敏度高。

Ultrasonic inspection of the baffle bolts,which are an important part of the internal structure of the reactor core,is faced with difficulties due to structural characteristics of the fastening pin,the complex structure of the contact site in the testing,and the limited space for contact coupling of the probe.In order to effectively identify the bolt thread reflection signal and the bolt shoulder defect,an innovative probe design and signal analysis method was initiated for the wall bolts.Blind test was performed by the inspection system for real bolts and it was shown that the examination sensitivity was relatively high.