Technology Focus: Cementing/Zonal Isolation (May 2018)

Abstract

Technology Focus Zonal isolation achieved with cement remains fundamental to well integrity for the full well life cycle. As I read through the abstracts and papers that have been presented in the past year, I notice several key themes: verification of cement placement, development of new materials as a barrier, development of new additives to improve the cement barrier, and enhancement of existing techniques. The fact that we are still studying and improving the cement barrier underscores how important it is as wells are pushed to new limits. Cement-job-performance indicators are critical. From our surface observations, surface sensors, and equipment performance, we can anticipate where zonal isolation is expected. With a robust cementing process embedded in the drilling process, we can be confident in the placement of the barrier. Paper SPE 188295 includes a very complete case history. Many efforts have been made relating to measurement of the outcome of cement jobs. New, more-powerful logging tools; better algorithms; and novel explanations are explored for each scenario that we can imagine. Paper SPE 188274 includes an excellent summary of today’s state of the art. Our industry continues to challenge drillers to push to new limits, which requires cementing technology to reach those same limits so that annular isolation can be achieved in every well that is drilled. Extended-reach wells are reaching new lateral-reach records. Managed-pressure drilling is a technique that is spreading, which logically leads to the need for managed-pressure cementing (MPC). Paper OTC 28139 includes a case history of MPC in deep water. Zonal isolation continues to be enhanced. The recommended additional reading provides an insight into a few of these enhancements, including abandonment practices, reverse cementing, and nanotechnology. Recommended additional reading at OnePetro: www.onepetro.org. SPE 185938 Perforate, Wash, and Cement (PWC) Verification Process and an Industry Standard for Barrier-Acceptance Criteria by Laurent Delabroy, Aker BP, et al. OTC 27864 Development and Validation of a Hydraulics Simulator for Estimating Subsurface Reverse-Cementing Placement Pressures by C. Wreden, Weatherford International, et al. OTC 27893 Development of Nanotechnology Pipe Treatment To Improve Acoustic Cement Evaluation by James Heathman, Shell International Exploration and Production, et al.