Many wells in the Cana-Woodford shale suffer from chronic sustained casing pressure (SCP) because of poor cement-sheath bonding. Using simulation software, centralization of the production casing was evaluated, and an optimized frictional pressure hierarchy was then designed. The engineered placement method ensured complete cement coverage around the casing through an optimized frictional pressure hierarchy. This multilayered approach using mechanically optimized slurries with different mechanisms of action, including self-healing, provided a comprehensive cementing portfolio that contained layers of contingency.
Introduction
One of the major operators in the Cana-Woodford field experienced poor bond logs and SCP both before and after stimulation, with the greatest number of issues appearing after stimulation.