Optimization of heat treatment of 30Kh13 steel for oil industry to operate in hydrogen sulfide environment: analysis of accelerated and standard tests

This study is devoted to the analysis of the general operational H2S-sphere of mechanical properties of martensitic stainless steel 30Kh13 (UNS S42000), widely used in the oil industry of Russia and abroad. The study includes a proposed methodology for preliminary analysis of the degradation of mechanical properties of hydrogenated samples as a result of long-term standard test method “A” NACE TM0177. Particular attention is paid to a comparative analysis of the parameters of the carbide phase of the microstructure and degradation of the mechanical properties of 30Kh13 steel samples depending on two heat treatment (HT) options — hardening at 1050 °C followed by the previous tempering at 680 °C and hardening at 1050 °C followed by ultra-high tempering at 780 °C. The preferred option for heat treatment of steel 30Kh13 for conditions containing hydrogen sulfide has been selected and justified. The results of resistance of steel 30Kh13 under stress in an extremely saturated H2S environment are presented. Research shows that the results of preliminary analysis correlate with the results of long-term standard tests according to NACE TM-0177, and the proposed methods can serve as an effective tool for selecting heat treatment modes, reducing time and costs at the initial stage of research. However, to confirm the results and the reliability of the materials, it is necessary to adhere to generally accepted standard criteria that have proven their reliability.The article was prepared with support of JSC ELKAM-Neftemash, as well as with the active participation and assistance of Doctor of Engineering Sciences Yu. N. Simonov.