TOFD技术对球罐近表面裂纹的检测

摘要

利用TOFD技术对球罐焊缝进行检测是一种行之有效的方法，但是由于受到直通波盲区的影响，球罐近表面裂纹容易被漏检。现场检测中通过减小PCS可以减小直通波盲区的影响，改变检测面甚至可以消除直通波对近表面裂纹信号的影响，从而使近表面裂纹等危险缺陷不至于漏检。%TOFD Technology is an effective method of spherical tank welding detection, but due to the influence of the direct wave blind areas, cracks near spherical tank surface are easily missed. Effects of PCS can be reduced by reducing the direct wave blind spot detection, Changing the detection surface can even eliminate the interference of near surface lfaw signals, so the cracks near surface and other dangerous defects will be not missed.