Abstract
The life cycle of a well is not static; throughout the stages, several changes in downhole conditions occur that can affect the integrity of the well. Common activities performed during the construction of the well (e.g. changes in density of the drilling fluids or an increase in temperature while drilling) may have an impact on the achieved cement isolation. During completion activities including stimulation and fracture treatments and even during abandonment activities, the well is exposed to diverse stresses that can damage the hydraulic isolation achieved with the cementing jobs. This document reflects the main steps for a general design process to achieve long-term isolation developed for deepwater development fields in the Gulf of Mexico, specifically at the production stages. This study includes an interdisciplinary study of geomechanics data from the formations, current drilling techniques, and data from downhole sensors at exploratory wells in the area that allowed for better understanding of how the resulting stresses can affect the interaction between formation, cement sheath, and casing, and provides information to design the required cement systems for the development fields.
