Cementing the casing and liner strings in place in oil and gas wells is integral to wellbore architecture, which in turn is integral to well performance and total hydrocarbon recovery. Conventionally, cementing is viewed as a one-time event, yet it serves as a foundation for ultimate recovery if engineered to withstand pressure and temperature differentials during life of the well events such as completion operations, fracture stimulation, and production cycles. In other words, rather than simply being the last step during drilling operations, it is economically more beneficial to view cementing as the first step in completion operations.
The cement sheath can be subject to thousands of psi (pounds per square inch) pressure changes and hundreds of degrees of temperature changes (Fahrenheit) throughout the life of the well. In spite of such dynamic fluctuations, the cement sheath is expected to resiliently withstand immediate and cumulative stresses, retaining seal integrity to securely isolate producing zones and restrain unwanted fluid production.
Today's and tomorrow's reservoirs are deeper, hotter and under higher pressure than yesterday's easy oil. Subsequently, wellbore challenges and achieving wellbore integrity are more complicated than ever before. These wells are likely to push or exceed the standard operating envelopes. Thus, Halliburton offers cementing systems designed to mitigate the effects of extreme loads imposed on the cement sheath in order to help avoid debonding from the casing or shear deterioration in the cement sheath.
Along with robust cement systems, Halliburton offers engineered-design models and simulations to augment information operators can use during the wellbore-architecture decision-making process. The integrity of the cement sheath should be considered during the design stages of well construction so that the well design provides uninterrupted, safe and economical production.
Halliburton also offers Swellpacker® Isolation Tools that can be placed at strategic points in the wellbore. When used with a primary cementing job, Swellpacker Isolation Tools provide an effective means of addressing microannulus concerns. This is a technically viable option in the event such as cement debonding from the casing and hydrocarbons attempt to flow through the created gap/microannulus. Instead of the hydrocarbons flowing unabated through the microannulus, they activate the swellable elastomer upon contact to close the microannulus and thus re-establish the hydraulic seal required.