Implementation of Key Reliability Indicators Led to a Reduction of Inactive Strings Count. A Lesson Learned in a Major Middle East Oil Company

Abstract This paper demonstrates lessons learned of adopting reliability indicators such as Mean Time Between Failure (MTBF), Mean Time To Failure (MTTF), Well Failure Rate (WFR), and MTTR (Mean Time To Repair) for managing wells under the context of well Inactivity. Historical data and statistics are analyzed and correlated at all Company Levels. The study unlocks the potential of re-directing the strategy of monitoring the well reactivation performance, resources planning and inactive strings prediction for certain Well inactivity categories. Reliability indicators (Level 2 KPI's) were introduced to enhance the management of Inactive wells. Historically, other metrics were used to measure the Company performance in terms of number of inactive strings over the total of number of operating strings on monthly/yearly basis. This approach is continued but is now complemented. Well Inactivity data starting from Jan-2016 until Dec-2023 was used to estimate MTBF, MTTF, Well Failure Rate, and MTTR at Company, Assets, Field and Well levels. Formulas and general assumptions will be described in the paper. Reliability metrics are usually applied to equipment (pumps, compressors, etc.) within specific conditions, this study doesn't intend to contradict or bypass the well stablished pertinence of those indicators. The assumption is to consider a Well as unique ecosystem that is composed of multiple sub-systems, and when the well is not able to sustain production for at least 7 days during a month, then this condition is counted as a failure. Implementation occurred within a specific module (Level 2 KPI Module) contained in the Inactive Strings Management System (ISMS), a comprehensive web-based application created internally and fully implemented throughout the Company. For further details on ISMS, see SPE-211040-MS. Adopting level 2 KPI's has revealed the potential of re-directing the strategy of monitoring the well reactivation performance, resources planning, and inactive strings prediction for certain well inactivity categories. It supported the reduction of the inactive strings stock by improving the estimation of required resources such as manpower, rig & rigless units, and surface actions. Furthermore, they have been instrumental in constantly revisiting the Company's business plan and ensuring inactive strings year-end targets can be exceedingly met. By incorporating these advanced reliability indicators into the management process, the Company has gained a more granular understanding of the underlying issues causing well inactivity. This strategic shift has led to more targeted interventions and optimized resource allocation, ultimately enhancing the overall efficiency and effectiveness of well operations.