对于电站锅炉受热面小径管焊缝接口的射线检测, 由于其管排结构及检测效益问题, 使得分段多次透照方法不适用。按照有关检测规程, 采用椭圆透照法对其进行检测。通过理论分析得出在管径、理论焦距及焊缝宽度一定的情况下, 焊缝影像的开口间隙仅与透照角度相关。通过自制的角度指示计, 对X射线检测设备进行了改装, 并运用于实际检测中。结果发现, 通过对透照角度的控制, 焊缝影像的开口间隙得以保证, 提高了根部缺陷的检出率; 角度计的使用灵活、方便, 减小了测量误差, 缩短了测量时间, 提高了工作效率, 具有一定的推广价值。

Considering the structure of pipes and cost of the inspection, the several times radiation method can not be used in the RT for small diameter welding tubes in utility boiler. According to the related standard, the elliptical RT method was used. Through the theoretical analysis, it was concluded that, the opening gap of welding image was only related to radiation degree, when the diameter, theoretical focus and width of welding were determined. The X-ray testing system was refit with a self-designed goniometer, and was used in the real testing. The result showed that, the opening gap of welding image was guaranteed and the detection rate of defects in root were increased. The goniometer was flexible and convenient to use, decreasing the measuring time and increasing the working efficiency, and was worth while popularizing.