Technology Focus: Completions
Authors: Lehr Doug 
Published: March 2019

Technology Focus
Are You There Yet?
For the optimal completion system, does “there” mean customization, standardization, or component modularity? Does it mean maximum reservoir contact or maximum surface contact? More or fewer clusters? Does it mean a completion that uses many compartments or fewer compartments? Are modular components part of the solution? In practice, optimality could include any or all of these.
Business as Usual?
More than ever, the industry needs reliable, flexible, cost-effective completion solutions. Increasingly, completion experts must think creatively to improve the performance and longevity of a completion system so that it achieves economic targets with reliability.
A recent analysis using an Eagle Ford data set investigated the relationship between rock brittleness and proppant bridging. The conclusion revealed that conventional thinking on cluster spacing and shot density must be challenged to improve injectivity and to realize the potential of the fracturing program.
Simulation
Fracturing design is in its third generation in the Bakken and is being driven by analysis that combines legacy production data, legacy zonal spacing, and offset-well data. One author is reporting increases in oil production in the range of 300 to 400%, while achieving lower water cut. Given the steep decline curves typical of these wells, this work cannot be ignored.
Design, Process Risk Assessment
The use of risk assessment in completion design is growing; it is no longer just for offshore applications. Those who acknowledge this are (correctly) advocating for its inclusion in the earliest stage of the completion process. Some authors observe that operational risks and consequences must be considered in the planning phase, rather than the execution phase, for maximum benefit. An example is the use of risk assessment for completion installation in wells with tortuous paths. It is probably not news that the drilling of wells with very tortuous paths is increasing. However, rather than hope for the best during installation, it is now possible to model and simulate beyond caliper data and dogleg severity to understand what must be done to place the completion bottomhole assembly at depth in good working condition.
Force Multipliers
How are results such as higher oil production and lower completion cost being achieved in an industry with fewer human resources and shorter project schedules?
Multidisciplinary project teams are one force multiplier. Such teams enable early understanding of formation, drilling, and completion interactions. This knowledge leads to earlier optimization of the completion system, when it is cost-effective to make the necessary changes. Subject-matter-expert input at this stage of the completion design process eliminates or reduces risk.
Standardization and modularity in component and system design are two other multipliers. Modularity offers the potential to simplify system design, and standardization offers the potential for operational flexibility. Although these are an aid to the operator, both can lead to improved delivery schedules from suppliers.
Summary
My conclusion is that we are on a good path but much work remains. To achieve better than good completion design, we must accelerate our use of all the tools and processes available—traditional and nontraditional. To get “there,” what also is required is the application of more simulation, increased emphasis on extracting the value from large legacy data sets, and the use of risk management in the planning phase. The result will be truly optimized completion design and improved project economics.
Recommended additional reading at OnePetro: www.onepetro.org.
SPE 191767 Redefining Bakken Completions: A Tailored Approach to Stimulation by Kyle Trainor, NP Resources, et al.
SPE 191390 Completion and Stimulation Design of the First Offshore Acid- Fractured Multistage Dual-Lateral Well by R. Oberhofer, Packers Plus Energy Services, et al.