Numerical modeling of rupture disk as a method of controlling pressure in oil well annulus

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The work objective is to present a methodology for computational modeling for pressure control in confined annulus of oil wells using rupture disks. Throughout the oil wellbore cycle life, different operations cause variations in its temperature, causing pressure increases in its annular spaces, a phenomenon called APB (Annular Pressure Build-Up). In some cases, the difference between internal and external pressures on the casing or production columns can result in the loss of their respective integrity caused by burst failure or collapse. When using a rupture disk, once the pressure difference over the column is greater than the disk collapse pressure, there is a hydraulic communication between the annulus, balancing the volume and pressure between them. This pressure balance significantly increases the safety factors of the coatings, whether for burst failure or collapse. The methodology adopted to achieve the objective of this work consists of five macro steps: i) bibliographical review on the use of rupture discs in the context of APB, identifying their functioning and advantages; ii) definition and numerical implementation of pressure balance models following those available in the literature; iii) simulation of a reference scenario to verify pressure balance models; iv) simulations of variations in the rupture disc positioning in the reference scenario and calculation of the casing safety factors (burst and collapse); and v) final evaluation of the disk's ability to control annular pressures and protect the casings. The results indicate that the proposed methodology presents good results compared to the state-of-the-art. Additionally, possible modeling adjustments can allow a closer approximation to reality in the field. The main work contribution is to advance studies on pressure control methods in annular using a methodology proposed in the literature. In addition, to developing a computational tool that reproduces this methodology.