APB mitigation in oil wells by open shoe, compressible foam, and rupture disk methods.

Annular Pressure Build-up (APB). APB mitigation methods. Oil wells.

This work aims to study some methods for mitigating the pressure increase in oil wells (APB - Annular Pressure Build-up). Over the life of the well, different operations provoke variations in its temperature, causing pressure increases in its annular spaces. In some cases, the increase pressure can lead to collapse failures of the casing. Drillings in ultra-deep areas face more extreme temperature and pressure conditions, increasing the levels of APB observed. In this context, mitigation techniques appear as alternatives to ensure the integrity of the well, keeping APB levels within the allowed limits. The methodology adopted to hit the objective is based on four macro steps. In the first stage, the study on the APB is accomplished, where the theoretical and mathematical aspects are identified. In this step, is accomplished the study of the simulator for estimate the APB, developed by Vasconcelos (2019), which is used in this work to evaluate the APB in wells. In the second step, a study is carried out on the mitigation methods of the APB, knowing the operation, advantages and disadvantages of each technique. In this step, the open shoe, compressible foam and rupture disk methods are selected for more advanced studies, due to the costs, applicability and reliability associated. In the third step, computational routines to reproduce the behavior of the APB with the presence of each of the three selected techniques are implemented in the simulator. In the fourth step, the results between the three methods are compared using graphs and tables. In this context, the present work contributes to the studies of APB and its mitigation techniques, presents computational implementations of the three mentioned methods and provides the simulator developed by Vasconcelos (2019) alternatives that are used in the field during operations in oil wells.