Abstract
For the construction of field oil pipelines, pipes made of 09ГСФ and 13ХФА steels corresponding to the strength class K52, are most in demand. Increased requirements are imposed on the resistance to the effect of ag- gressive media containing water and hydrogen sulfide of pipe products and fittings of field oil and oil product pipelines. JSC Ural Steel has successfully implemented a unified integrated process for the production of corrosion-resistant plates made of 09ГСФ and 13ХФА steel grades with a wide range of sizes, meeting the requirements for hydrogen-induced cracking according to the NACE TM0284 standard and sulfide stress corrosion cracking according to method A of NACE TM0177 standard. Controlled rolling patterns with accelerated post-deformation cooling and subsequent high tempering have been developed, which provide a specified level of mechanical characteristics corresponding to the strength class K52. To ensure satisfactory flatness of plates, variants of chemical composition of steel are recommended depending on the thickness of the finished plate. Production modes provide high cold resistance of steel and actual val- ues of impact toughness KCV–40 that significantly exceed regulatory requirements. It is shown that a decrease in the Ca/S ratio in steel down to ~ 0.6–1.0 with a sulfur content of less than 0.002% does not only lead to a decrease in corro- sion resistance, but also minimizes the segregation inhomogeneity of the steel and contamination with non-metallic in- clusions. The process developed at JSC Ural Steel provides the possibility of industrial production of corrosion-resistant plates made of 09ГСФ and 13ХФА steel grades with a wide size range.
Key words: secondary metallurgy, corrosion resistance, hydrogen-induced cracking, hydrogen sulfide cracking, controlled rolling, accelerated cooling, high tempering, microstructure.