As operators continue drilling longer laterals, current completion methods present challenges in maximizing stage counts while maintaining operational efficiency and minimizing operational risk. This paper will discuss recently developed completion systems, the Ultra-High Stage Count and the Latch-and-Perf Systems, and results in addressing completion challenges from field trials.
Some of the inherent risks and challenges associated with the current completion methods include: (i) reaching the toe of long laterals with coiled tubing and wireline for setting, stimulation and millout operations; (ii) maintaining a full inside diameter during stimulation for an effective treatment; (iii) time and cost efficiencies; and (iv) logistics. The pros and cons of multiple completion technologies will be highlighted, including various sliding sleeve completion methods in both openhole and cemented applications, as well as plug-and-perf completions.
Design considerations, bench testing and field trials related to the Ultra-High Stage Count System and the Latch-and-Perf System will be presented. The Ultra-High Stage Count System uses pump down sleeve activation tools that build on the efficiency and cost savings associated with continuous pumping operations, requiring no downtime between stages as a unique latch-functioned sleeve actuation tool is pumped from surface to land and shift a corresponding sliding sleeve in the wellbore. Using full diameter sliding sleeves provides no restriction in the wellbore during treatment, maximizing pump rates. The Latch-and-Perf System also provides a full diameter during stimulation and uses a latch isolation tool deployed on wireline to isolate a stage for perforating and treatment, eliminating the requirement for plug setting and millout operations. Both systems are currently in field trials.
The novel Ultra-High Stage Count System presents a step-change in completion design as it overcomes challenges presented by drilling longer laterals without comprising any of the efficiencies and benefits from today's current completion technologies.