Enabled Resuming Drilling, Run Liner and Cementation by First Distinguishing from Kick and then Overcoming Extreme Ballooning Conditions in a Controlled Environment, Navigating Through Ultra-Narrow Window in Abnormal Pressure Wells by Implementing Managed Pressure Techniques

Abstract

High-pressure and narrow window drilling environments can present significant challenges by themselves but having extreme ballooning at the same time requires a sophisticated strategy to complete the well, since well control cannot be overlooked by assuming it is ballooning. These simultaneous hazards lead to delays in drilling operations, as it is difficult to maintain a stable wellbore pressure using conventional techniques. As a systematic solution, the managed pressure well technique was implemented. Managed pressure technique is a comprehensive wellbore pressure management solution that combines managed pressure drilling (MPD), managed pressure running liner (MPRL), and managed pressure cementing (MPC) to improve the efficiency and safety of drilling operations. This paper presents a case study of the successful implementation of MPW in a narrow window, HPHT well. Prior to MPW operations, the operator faced unexpected hazards, including background gases and false interpretation of well flow, leading to an increase in mud weight up to 153pcf. Extensive well fingerprinting was used to differentiate flowback from influxes and establish the available window, based on which drilling, tripping, liner running, and cementing operations were designed and successfully performed. Careful displacement of kill mud in stages made it possible to run the liner, without inducing surge or mud losses.

The results and findings of this case study demonstrate the efficacy of Managed pressure technology in narrow window, HPHT wells and provide a foundation for future applications of this technique in similar drilling scenarios. Prior to call MPD services, around 15 days were spent as non productive time for well control situation. False interpretation of well control lead to wasting time, mud and associated costs. Conventional drilling in this scenario could have resulted in a simultaneous kick/loss situation and increased nonproductive time and cost. The novel MPD approach employed in this case allowed for the systematic bleeding of the well in a controlled environment enabling the use of lighter mud weights, hence overcoming extreme ballooning and achieve the well objectives. The case study also highlights the importance of mud weight selection, surge swab, and bottomhole pressure optimization during liner trip and cementing operations.