Ultrasonic inspection of welded joints of the pipeline type DN800. Part II

In the first part of the article, it is shown that in order to restore a high-quality image of reflectors in a welded joint of a pipeline of the Du800 type, it is not enough to use the CFA method in a variant designed for the propagation of ultrasound in a homogeneous isotropic medium. To further improve the image quality in the CFA method, it is necessary to: determine the elastic properties of the surfacing of the Dn800 pipeline and take into account its anisotropy during ultrasound propagation, as well as the surface profile. To increase the resolution and reduce the noise level, the CFR-H and maximum entropy (ME) methods were applied. Comparison of the results of ultrasound and X-ray controls allowed us to conclude that the first of them is more informative for detecting crack-like reflectors.