Carbon steels, used in pipelines for the transport of oil and its derivatives, are frequently exposed to fluids. This can result in stress induced corrosion cracking (SCC) and/or hydrogen embrittlement (HE). The present paper evaluates the susceptibility of pipeline steels (API-X70 and API-X80) to SCC and HE, using a slow strain rate test (SSRT) based on the National Association of Corrosion Engineers’ (NACE) norm and a traditional standard NACE test. The (SSRT) method used, employed a sodium thiosulphate solution to evaluate susceptibility to HE, thereby offering a simpler experimental procedure than the standard NACE test. The results confirm the efficacy of the sodium thiosulphate as an H2S–SCC susceptibility test solution when utilised in SSRT testing. Though no secondary cracks were detected in the materials investigated, both steels were observed to suffer a ductility loss upon exposure to this solution. In NACE type tests, the test pieces were subjected to constant loading at 80% of σy. Fracture did not occur for these samples.

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