核电厂监督区射线探伤对主蒸汽管道辐射监测仪表影响的分析与防护研究  

Analysis and Protection Study on the Impact of Radiographic Flaw Detection in Nuclear Power Plant Supervision Area on Radiation Monitoring Instruments of Primary Steam Pipes

作　　者：易柏元 董海斌 YI Boyuan;DONG Haibin(Jiangsu Nuclear Power Co.Ltd.,Health Physics Department,Lianyungang,Jiangsu Prov.222000,China)

机构地区：[1]江苏核电有限公司,江苏连云港222000

出　　处：《中国核电》2025年第1期52-58,共7页China Nuclear Power

摘　　要：核电厂为监测一回路放射性物质是否泄漏到二回路,在主蒸汽管道旁设置4台γ探测器连续监测主蒸汽的γ剂量率,报警后通过四取二表决将直接触发机组停堆信号。该仪表位于蒸汽厂房,机组日常运行及大修期间控制区外围射线探伤可能会导致该仪表位置辐射水平升高,存在触发机组保护停堆信号风险。本文通过研究VVER机组监督区射线探伤对主蒸汽管道辐射监测通道的影响范围和途径,采取增加可移动铅屏蔽门的方法避免了由于射线探伤作业可能导致停堆信号触发的风险,对后续同类机组的设计与运行提供了有益的参考经验。In order to monitor the leakage of radioactive substances from the primary circuit to the secondary circuit,four gamma detectors are set up next to the primary steam pipeline to continuously monitor the gamma dose rate of the primary steam,and the alarm will directly trigger the shutdown signal of the unit through two of four voting.The instrument is located in the steam building,and the radiographic inspection outside the control area during the daily operation and overhaul of the unit may cause the radiation level at the instrument position to rise,and there is a risk of triggering the unit protective shutdown signal.In this paper,the influence range and the way of radiographic inspection outside the radiation control area of VVER unit on the radiation monitoring channel of the primary steam pipeline are studied,and the risk of shutdown signal triggered by radiographic inspection operation is solved by adding the lead shield door,and provides useful reference experience for the design and operation of similar units in the future.

关 键 词：射线探伤 辐射监测仪表 屏蔽 

分 类 号：TM623[电气工程—电力系统及自动化]