AP1000核电机组的设备闸门是大型设备进出核岛的必要通道。该机组设备闸门由于补强板钝边位置超差，焊接完成后，部分焊缝宽度超宽，厚度比过大，甚至超过了X射线机的最大透照厚度，给射线检测带来了很大的困难。讨论了这种特殊情况下的射线检测方案，通过现场测量焊缝的宽度和厚度，建立焊缝立体模型并制定了设备闸门补强板焊缝射线检测的最佳方案，并进行了检测试验，得到了较好的检测效果。

The equipment gate of AP1000 nuclear power unit is a necessary passage for large scale equipment to enter or exit the nuclear island. However, the blunt edge position of the stiffening plate in equipment gate of this unit is sometimes out of tolerance after soldering, and part of the weld width is over wide and the thickness ratio is too large, even beyond the X-ray machine maximum transmission thickness. It caused great difficulty for radiographic testing. In this paper, the scheme of radiographic testing in this special case is discussed, and by measuring the width and thickness of weld on site, a solid model of weld seam was established and the best scheme of radiographic testing for weld seam in the stiffening plate of equipment gate was formulated. The test was carried out and a better effect was therefore obtained.