Best Practice in Understanding and Managing Lost Circulation Challenges

TLDR

Lost circulation causes significant nonproductive rig time, and recent advances have shifted focus from plugging to borehole strengthening using rock mechanics, improving understanding and success rates. This review examines the current status of lost‑circulation approaches, addressing controversial points and comparing proactive and corrective strategies. The authors analyze both proactive and corrective methods, evaluating their rock‑mechanics basis and operational pros and cons.

Abstract

Summary Lost circulation has been one of the major challenges that cause much nonproductive rig time each year. With recent advances, curing lost circulation has migrated from "plugging a hole" to "borehole strengthening" that involves more rock mechanics and engineering. These advances have improved the industry's understanding of mechanisms that can eventually be translated into better solutions and higher success rates. This paper provides a review of the current status of the approaches and a further understanding on some controversial points. There are two general approaches to lost circulation solutions: proactive and corrective, based on whether lost circulation has occurred or not at the time of the application. This paper provides a review of both approaches and discusses the pros and cons related to different methods—from an understanding of rock mechanics and operational challenges.