Low-alloy steel with elevated strength for apparatuses for complex preparation and processing of natural gas containing hydrogen sulfide

Apparatuses for complex preparation and processing of hydrogen sulfide-containing natural gas are commonly produced from carbon steels of the 20Yuch type. However, the strength level of these steels is low (σ_0.2≥240 N/mm²). Low-alloy weldable steel 09G2S has a higher strength, namely, σ_0.2≥300 N/mm² for rolled stock up to 32 mm thick and σ_0.2≥275 N/mm² for rolled stock up to 80 mm thick. At the same time, steel 09G2S has a low cold strength (the semibrittleness temperatureT ₅₀≥−30°C) and a low resistance to hydrogen sulfide cracking (the threshold stress σ_th=0.6σ_0.2). The present paper is devoted to the effect of the composition and structure on the set of properties of new low-alloy plate steel 09GSNBTs, which possesses elevated strength and is resistant to hydrogen sulfide cracking. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 2–5, February, 1997.     

Structural parameters of structural steel determining its resistance to hydrosulfuric cracking

Conclusions To attain high resistance to hydrosulfuric cracking of steels for drive pipes, it is necessary after heat treatment to attain a structure with the following parameters: size of the coagulated carbide (M₃C) particles d0.05 m to eliminate the possibility of nascent hydrogen accumulating on the carbide-matrix interfaces; subgrain size d>0.30 m to ensure relief of internal stresses, and dislocation density p<-10⁹ cm^–2 to eliminate places of possible localization of hydrogen.I. P. Bardin Central Research Institute of Ferrous Metallurgy. Siberian Branch of the Special Design Bureau of the Scientific and Production Association Soyuzgazavtomatika, Saratov. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 11, pp. 19–20, November, 1991.     

Effect of tempering at subcritical temperatures on the fracture strength of medium carbon structural steel

A special pretransformation state in steels is of considerable interest and importance for practical application.Difficulties arising from the necessity for precise temperature regulation have already been overcome incontemporary heating equipment. In this article certain features of this pretransformation state are explainedor confirmed, and the utility of its application in heat treatment is described.Bardin Central Scientific Research Institute for Steel Metallurgy. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 8, pp. 10–13, August, 1992.