γ射线探伤机表面漏射线防护装置的设计与应用

Design and Application of Surface Leakage Protective Device of γ Ray Detector

目前国内γ射线探伤机主机体(源容器)的屏蔽性能要求应符合GB/T 14058-2008标准,也就是γ射线探伤机主机体表面的辐射当量剂量率不能超出2000μGy/h,此数值比射线探伤作业场所控制区允许的辐射当量剂量率限值高出133倍。工作人员在操作γ射线探伤机时,不可避免要近距离接触γ射线探伤机,相比控制区增加了工作人员的受照剂量,给探伤工作人员造成一定伤害和心理压力。针对这种问题设计了一种可减小γ射线探伤机表面漏射线的防护装置,以减少工作人员受照剂量,从而增加接触时间,提高检验效率,减小对工作人员的伤害。试验结果表明:在TS-1A型铱-192γ射线探伤机和TS-1B型钴-60γ射线探伤机上安装屏蔽防护装置后,可以将主机体表面辐射当量剂量率减小约150倍和90倍。

At present,the shielding performance requirements of γ ray detector(source container)in China should meet GB/T 14058-2008 standard,that means the radiation equivalent dose rate on theγray detector surface should not exceed 2000μGy/h,which is 133 times higher than the allowable radiation equivalent dose rate limit in the control area of radiographic detection work site.When operating the γ ray detector,operator inevitably have close contact with the detector,which increases the exposure dose compared with the control area,causing certain menticide and psychological pressure to the operator.This paper designs a protective device which can reduce the radiation leakage on the surface ofγray detector,reduce the radiation dose of the operator,consequently increasing the contact duration,improving the inspection efficiency and reducing the menticide to the operator.