Study on the Influence of Perforation Parameters on Downhole Casing During Hydraulic Fracturing

ABSTRACT: During oilfield development, casing deformation has become a significant factor affecting operational efficiency and long-term production. Specifically, in fracturing operations, perforation can significantly reduce the casing strength in the perforated zone, thereby increasing the risk of downhole casing deformation. This study employs a finite element analysis approach to establish a three-dimensional coupled analysis model that considers the interaction between the reservoir, cement sheath, and perforated casing. Utilizing this model, we analyze the deformation of the casing under different perforation parameters. The results indicate that the perforation holes and the casing ends are the primary deformation zones after perforation. Within a certain range, as the spacing between perforation clusters increases, the impact of perforation on casing deformation gradually diminishes. Additionally, a smaller perforation phase angle can lead to greater casing deformation and residual stress. Furthermore, during the fracturing process, the pumping pressure during the crack propagation phase is the primary factor affecting casing deformation, and the magnitude of the pumping pressure positively correlates with the Mises stress and deformation exhibited by the casing during operation.