摘要
通过分析声波传播特性、检测信号及图像特征,提出20°探头的超声衍射时差法(TOFD)检测模式,并研制20°探头。通过对比5 MHz及2.25 MHz这2种频率下检测效果,进行优化试验。然后通过对不同的内壁模拟缺陷进行检测,制定适合厚壁承压容器内壁缺陷的最佳TOFD检测工艺。试验表明:在核电厂厚壁承压容器内壁缺陷TOFD检测中,20°探头、5 MHz频率是最佳选择;在此检测工艺下,对壁厚120 mm以内的承压容器,能够检出内壁缺陷的最小临界尺寸高为2 mm。
The 20° probe is proposed in order to optimize the TOFD detection. Acoustic wave characteristics, detection signal and image feature of 20° probe are analyzed. The oPtimal frequency is determined by comparing 2.25MHz and 5MHz. Through TOFD detection of artificial inner surface defect, the optimum detections are demonstrated, which are fit for detecting thick-walled nuclear pressure vessel with inner surface defect. The experimental results show that： （a） for thick-walled nuclear pressure vessel with inner surface detect, 20~ probe and 5MHz frequency are optimization. （b） By this optimization detection, artificial inner surface defect with height of 2mm can be effectively distinguished in nuclear pressure vessel with thickness of 120mm.
出处
《核动力工程》
EI
CAS
CSCD
北大核心
2014年第2期79-83,共5页
Nuclear Power Engineering
基金
中国国电集团公司重大科技专项(GDJJ2012[84])
关键词
TOFD
检测优化
厚壁
承压容器
细晶材质
内壁缺陷
TOFD, Detection optimization, Thick-walled, Pressure vessel, Fine grain material, Inner surface defect
