Emergency plugging of shear ram failure

Abstract

Well control (pressure control of the wellbore) plays a crucial role in drilling engineering. As a key equipment in well control, a blowout preventer (BOP) does not only control the wellbore pressure but also serves as the last barrier to well control. Although prevention is the best method to eliminate risks, unexpected failure risks remain in harsh environments, and once the BOP fails, it can result in serious accidents. Therefore, an additional control measure will ensure well control safety. Based on the investigation of the main failure elements and failure forms of the BOP, a simulation model was established in this study for emergency plugging of BOP failure. The reliability of the simulation model was validated through experiments using a high-temperature and high-pressure mud plugging instrument, and the possibility and influencing factors of urgent plugging were analyzed using this model. The results indicated that particles with a particle–pore ratio of 1.6 resulted in the most effective plugging under blowout conditions. The higher the particle concentration, the faster the plugging, and the longer the effective sealing time. Mixing the particles did not improve the plugging effect but can significantly increase the effective plugging time, which is beneficial for subsequent well killing. This study provides an additional means of well control assurance, which can serve as theoretical guidance for ensuring well control safety.