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Nowadays, an increasing number of oil and gas transmission pipes are constructed with high-strength low alloy steels (HSLA; nonetheless, many of these pipelines suffer from different types of hydrogen damage, including hydrogen-induced cracking (HIC). Many studies are being done to investigate the role of key metallurgical and processing factors to limit the negative effects of HIC in HSLA steel pipes. more...

Improvement of non-destructive inspection techniques has allowed more frequent detection of closely spaced zones of non-metallic inclusions in pressure vessels made of low carbon steel. In the present study, closely spaced inclusions in an in-service cylindrical horizontal pressure vessel were detected by Scan-C ultrasonic inspection and considered as laminations to be assessed by Part 13 of the API 579-1/ASME FFS-1 2016 standard. The outcoming results were considered as a rejection for Level 1 assessment, and a repair or replacement of the component was required, even though it retained a significant remaining strength. Thus, an alternative procedure to assess the mechanical integrity of pressure vessels containing zones of non-metallic inclusions is proposed by adopting some criteria of the API 579-1/ASME FFS-1 Part 13 standard procedure and taking into consideration the dimensions and grouping characteristics of the inclusion zones more...