The content of hydrogen sulfide in the extracted fluid is characteristic of the oil and gas fields of the Ural-Volga region and the Caspian Sea region. The presence of hydrogen sulfide has a high effect on the corrosion destruction of the structure of oil and gas field equipment, pipelines, etc. The article discusses the effect of the mechanism of sulfide stress corrosion cracking on the casing string. As a result of a preliminary analysis of the construction of wells at the fields of Orenburgneft JSC (the subsidiary of Rosneft Oil Company), the experience of casing pipes of conventional strength groups application in the presence of hydrogen sulfide in the reservoir fluid was established, and a decision was made to conduct research work. At the first stage of the work, operational facilities containing hydrogen sulfide in the reservoir fluid were identified; its volume content and partial pressure were established. Then, according to the actually constructed and designed wells, the levels of operating operational loads of axial tension and internal pressure are calculated relative to the value of the minimum yield strength of the material of the casing pipes used. According to the actual operating conditions of casing pipes in the presence of hydrogen sulfide in the reservoir fluid, technical requirements for them have been formed. The points of these requirements are confirmed in laboratory tests of samples from seamless casing pipes of the usual strength groups for sulfide stress corrosion cracking. The developed technical requirements for seamless casing pipes used in conditions of the presence of hydrogen sulfide in the reservoir fluid at the facilities of the company are used when additional requirements are presented both for the purchase of new pipes and for the qualification of available pipes.
1. Osobennosti rascheta obsadnykh i liftovykh kolonn gazovykh skvazhin, kontaktiruyushchikh s flyuidami, soderzhashchimi serovodorod. Rekomendatsii (Features of the calculation of casing and lift strings of gas wells in contact with fluids containing hydrogen sulfide. Recommendations), Moscow: Publ. of VNIIGAZ, 1989, 54 p.2.