This paper describes how the Pre-Salt reservoir monitoring & control requirements in Brazil, and the pressure to minimize CAPEX, OPEX, and ABEX pushed for the development of a cableless intelligent well completion based on reliability. The development plan proposed is associated with an appropriate risk assessment to ensure lower risk at each project phase.
The X-ware (hardware, software and human) reliability methodology is used throughout the development. It starts with a complete understanding of environmental and operational conditions, needed/requested materials and well design. Then, reliability assessments based on physics-of-failure methods is used to incorporate reliability into the hardware design process and continuous time non-homogenous semi-Markov process to capture human/software reliability. Finally, to ensure a lower risk at each project phase, complexity theory is used to evaluate the overall risk.
This development of a cableless intelligent completion addresses monitoring and control for up to four reservoir zones on producing, injection and convertible wells, all of them in a subsea environment where scaling and lost circulation problems are likely to happen. Reliability of at least 90% in 30 years with 80% of confidence interval is the major challenge of this development. The critical paths to ensure the achievements are cableless telemetry and the energy harvesting for the life cycle of the well. The expected results for the development are: expedite technology readiness with lower risk during installation and higher availability during the life cycle of the well.
The development of new technologies using X-ware reliability methodology and technical risk as a process control variable is the main contribution of this paper.