Numerical simulation method and structural optimization for shearing capacity of ram blowout preventers

With the increasing demand for energy in the country, there has been a notable rise in the deployment of deep and ultra-deep wells. Consequently, drilling operations have become more complex, with greater intricacies in drilling techniques, challenging operating conditions, and varying geological factors. The size of the drill pipes has grown larger, and higher steel grades are being used, surpassing the design requirements of conventional ram blowout preventers. As a result, issues have arisen, including inadequate shear force of the ram blowout preventer to cut through the drill pipes and the potential for cut debris from the drill pipes to fall and damage the sealing elements, compromising the sealing integrity and posing a risk of blowouts.To address these issues encountered in the field, a shear analysis model for the ram blowout preventer was established based on the Johnson-Cook constitutive model and the Shear Damage fracture criterion. The reliability and accuracy of the simulation were validated through comparative experiments between simulation and laboratory trials. Furthermore, the structure of the ram blowout preventer was optimized to mitigate these challenges. Additionally, the response surface method was employed to optimize the parameters of the novel ram structure for the ram blowout preventer, followed by indoor experiments using the selected parameters. The experimental results demonstrated a significant improvement in both the shear performance and sealing capability of the novel ram blowout preventer compared to the conventional ram blowout preventer design. This advancement provides valuable insights and practical reference for on-site operations.